EMBODIED EXPERIENCES IN IMMERSIVE VIRTUAL ENVIRONMENTS: EFFECTS ON PRO-ENVIRONMENTAL ATTITUDE AND BEHAVIOR A DISSERTATION SUBMITTED TO THE DEPARMENT OF COMMUNICATION AND THE COMMITTEE ON GRADUATE STUDIES OF STANFORD UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Sun Joo Ahn May 2011 ABSTRACT Immersive virtual environments (IVE) allow users experience vivid sensorimotor stimuli by digitally simulating sensorimotor information. As a result, users are able to embody experiences by seeing, hearing, and feeling realistic perceptual cues linked to those experiences. Embodied experiences are defined as being surrounded by simulated sensorimotor information in mediated environments that create the sensation of personally undergoing the experience at that moment. Based on the theoretical framework of embodied cognition, which stipulates a close connection between sensorimotor experiences of the body and mental schemas, the current dissertation studies demonstrated that embodied experiences in IVEs are able to influence attitudes and behaviors in the physical, non-mediated world. Two studies explored the effect of embodied experiences on proenvironmental attitude and behavior by having participants embody the experience of cutting down a redwood tree as a result of using non-recycled paper products. Focus was also placed on investigating individual elements of embodied experiences in IVEs and the moderating effect of individual differences in the capacity to feel presence, the perception that a mediated experience is real. In both studies, actual pro-environmental behavior is observed and compared to self-reports of attitude and behavioral intention. Study 1 (N = 47) compared embodying the tree-cutting experience in IVEs against mental simulation (MS) of the experience after priming participants with information on using non-recycled paper products and deforestation problems. Results demonstrated that participants in both experimental conditions experienced increased pro-environmental self-efficacy, or the belief that their individual actions could improve the quality of the environment. However, in terms of proiv environmental behavior measured by observation of actual usage of paper napkins, participants who embodied the experience in an IVE demonstrated greater paper conservation compared to those who merely imagined the experience. Analyses also confirmed that participants in the IVE condition felt greater presence and personal control during the embodied experience compared to those in the MS condition. Study 2 (N = 101) manipulated individual elements that could affect how participants embodied the tree-cutting experience in IVEs. Two independent variables were manipulated in two levels in the same tree-cutting context from Study 1 – immersion (i.e., number and degree of sensorimotor information provided to the user; High vs. Low) and agency of control (i.e., the agent who controls the movements of the saw; Self-Move vs. Other-Move). Results demonstrated that similar to Study 1, any form of embodied experiences increased pro-environmental self-efficacy. However, agency of control influenced how actual pro-environmental behavior was manifested in terms of paper conservation and this effect was moderated by individual differences in the capacity to feel presence. Individuals high in capacity demonstrated greater pro-environmental behavior when allowed to fully control the saw, whereas individuals low in capacity demonstrated greater proenvironmental behavior when they were allowed to let pre-recorded saw movements guide their hands while cutting down the tree. Perceptions of presence and control are also measured and analyzed to gain greater insight to the process of embodied experiences in IVEs. In sum, the current studies demonstrated that the vivid sensorimotor experience of seeing, hearing, and feeling a tree being cut down in IVEs as a result of using non-recycled paper products is powerful enough to influence actual paper consumption behavior in the physical, non-mediated world. v ACKNOWLEDGEMENTS So many people have touched my life, provided invaluable guidance, and showered me with an unbelievable amount of support and encouragement during my time as a doctoral student at Stanford that I almost feel as if this dissertation is a collaborative effort of all of my colleagues, friends, and family. These were arguably the most dynamic five years of my life, and as much as I hate the banality of this overused expression, time seems to have literally flown by, to the extent that the fact I am getting ready to graduate seems surreal, even. In just five years, I have managed to find my partner in life, marry him, obtain a doctoral degree, and secure a job as an assistant professor. Most importantly, as I write this acknowledgment while looking back at these emotionally-turbulent turning points of life, my husband and I are nervously and excitedly anticipating the very imminent arrival of our first son, Ryan Chu. It is obvious that graduation will also mean the beginning of topsy-turvy changes in my life as my new roles as an independent scholar and a new mommy commence. But before anything else, I think I should take a short moment to express heartfelt thanks and gratitude to the countless people who helped me grow both intellectually and emotionally through these events. Here at Stanford, I would like to thank my advisor, Dr. Jeremy Bailenson, for being there for me during every hesitant step I took toward becoming an independent scholar and researcher. He is the one who introduced me to the world of virtual reality, and with undying patience, allowed me to develop my own area of interest and to discover the joys of research. Most importantly, when something needed to be done as soon as possible; when I had a burning question; when I desperately needed advice – I knew I could depend on him without a shred of doubt. vi I cannot even begin to describe what a luxury this was during times of stress and uncertainty. I probably could not have come so far and grown so much in such a short span of time without his attention and guidance. I would also like to thank Dr. Cliff Nass for his ability to see the best in people. He always knew the right thing to say when I was just about ready to give up. Anyone can see that he genuinely cares about the welfare of students and his words of wisdom have a way of resonating in one’s heart for quite a long while. Dr. Byron Reeves must also be thanked for always knowing the “right” answer and for having strong faith in my work. He always found time to be a mentor in times of need despite his incredibly busy schedule and the advice coming from his long years of experience and expertise was invaluable. Special thanks to Dr. Christian Wheeler and Dr. Baba Shiv of the Graduate School of Business for reading this dissertation and providing insightful comments for improvement – the dissertation has now become a significantly stronger piece of work, thanks to their constructive inputs. Finally, I would like to thank Dr. Hunter Gehlbach for offering valuable insights on the theoretical questions leading to this dissertation, helping improve the actual study design, and providing his questionnaire items. Overall, I was blessed with incredible opportunities to consult with the best experts that the field has to offer both in and outside of Stanford and was constantly amazed at their willingness to help resolve my problems as if those problems were their own. Furthermore, this dissertation would never have been complete without the extraordinary support from all the programmers and research assistants of the Virtual Human Interaction Lab and the VRITS program. Many thanks to Crystal Nwaneri, Divij Gupta, Felix Chang, Huong Phan, Julio Mojica, Michelle Del Rosario, Oliver Castaneda, and Jim Zheng for working tirelessly to meet some vii unrealistic deadlines for the completion of these studies and always coming to the rescue in times of dreaded technical failures. Special thanks to Cody Karutz, the lab manager, who magically made everything happen, no matter how tight the timeline or how difficult the task. And thanks to everyone at the front office for dealing with the monstrous amount of paperwork associated with being a non-resident alien in the U.S. A big thank you to Susie Ementon who always had answers to every question I had – on documentation, procedures, life as a grad student, and yes, even on rearing babies. I would also like to thank all the other staff members, Barbara Kataoka, Mark DeZutti, Mark Sauer, Katrin Wheeler, and Lisa Suruki, for being helpful in every possible way. Outside of Stanford, I must thank Dr. Kyu-ho Youm for his mentorship ever since I first decided to pursue a doctoral degree and Dr. Eun-ju Lee for her words of wisdom on various aspects of life, including how to manage a decent work-life balance as a working mother. I look up to them as my role models both professionally and personally. Many thanks to all of the professors at the Department of Communication at Seoul National University, including Dr. Seunggwan Park, Dr. Seung-mok Yang, Dr. Joon-woong Rhee, Dr. Sug-min Youn, and Dr. In-cheol Choi who helped me set out on my journey at Stanford and believed in my potentials as an academic from the beginning. A special thanks to everyone at the Korea Foundation for Advanced Studies who provided me with an unbelievably generous fellowship for the past five years. It was an incredible luxury to be free from worrying about tuition, medical insurance, and living expenses for so many years and it allowed me to focus completely on research. Next, the reason I am able to look back at the past five years and can say viii without hesitation that I would take this path again even if I were given a second chance is because I was surrounded by wonderful family and friends who made what could have been the most stressful time of my life into unforgettable five years filled with cherished moments, friendship, love, and laughter. First, a big thank you to all of my friends in Korea. Although they could not be here with me in body, I could not have pulled through without their constant support via IMs, various social networking sites, long international telephone conversations, and good ol’ hand-written letters. Thank you for being there for me through thick and thin. I would also like to thank all of my Korean friends here at Stanford who kept me well fed and pampered. I feel that I have received so much more than I have given during the past five years and will never forget the incredible social support that all of you have shown me. It was amazing how every time that I felt I could not go on and wanted to pack my bags, there was someone out there ready to hold my hand and tell me that this, too, would all pass. I will never forget the experiences I had as the President of the Korean Student Association at Stanford, the late night movies and drinks, the potluck parties, and the countless hours spent pouring our hearts out over coffee and tea. An extra special thanks to the members of JAGH – Jesse Fox, Abhay Sukumaran, and Helen Harris – for their incredible support and friendship. You guys are the best cohort that a grad student could wish for. This dissertation could never have happened without your words of advice and encouragement, warm brownies, surprise gift and flower deliveries. I expect to see all of you in Georgia very soon. Thank you, Kathryn Segovia, for having more faith in me than I have in myself. You always tell me that I am a Superwoman, but I could never have done it without your happy smiles, cheesecake deliveries, amazing baby showers, and ix constant encouragement. You brought out the Superwoman in me. I would also like to thank Sean Westwood for his wry sense of humor and awesome cooking skills, and Ethan Plaut for sharing my quirky likes and dislikes of life. A giant hug and kisses to my parents, Kyu-Moon Ahn and Youn-Sook Cho, for being the best parents anyone could possibly want. I took it for granted for quite a while but now realize how incredible it is that there is not a thing I would change about my childhood or the way that I was brought up. You have always been the source of my strength and I just know that you will make everything better even in the worst of times. The greatest obstacle to obtaining my doctoral degree was the fact that I was only able to see you once or twice a year at most. And a great big bear hug to my little brother, Sun-chong (Richard) Ahn. Thank you for being so dependable even though you are my dongseng. Finally, I would like to dedicate this dissertation to my husband, Yeon Jin (Andrew) Chu, and my soon-to-be-born son, Ryan Chu. I love both of you more than anything else in the world. Yeon Jin oppa, you always tell me that the best decision you ever made in your life was to marry me. I have just three words in reply to that: back at you. x TABLE OF CONTENTS CHAPTER ONE: INTRODUCTION………………………………………………1 CHAPTER TWO: EMBODIED COGNITION AND EMBODIED EXPERIENCES……………………………….…………………………………….4 Neurological Evidence of Embodied Cognition…………………………..........4 Behavioral Evidence of Embodied Cognition………………………………….6 Mental Simulation………………………………………………………………8 Virtual Environments and Embodied Experiences……………………………..9 CHAPTER THREE: FUNCTIONAL FEATURES OF EMBODIED EXPERIENCES IN VIRTUAL ENVIRONMENTS………………………………12 Immersion…………………………………………………………………..…12 Interactivity………………………………………………………………...….15 Combination of Flexibility, Control, and Realism…………………………….17 CHAPTER FOUR: SUBJECTIVE FEATURES OF EMBODIED EXPERIENCES IN VIRTUAL ENVIRONMENTS………………...……………………………….22 Individual Differences in Presence Perception………………………………..27 Presence Perception in Different Modalities………………………………….29 CHAPTER FIVE: JUSTIFICATION FOR DISSERTATION STUDIES………….33 Different Modalities and Embodied Experiences………………………….….33 Processes of Embodied Experiences…………………………………………..37 Individual Differences in Embodied Experiences…………………………….38 CHAPTER SIX: DISSERTATION STUDY ONE: COMPARISION OF EMBODIED EXPERIENCES WITHIN IVE AND MENTAL SIMULATION.......41 Methods…..……...………………………………………………………..44 Results…......……………………………………………………………....54 xi Discussion……………………………………………………………………..58 CHAPTER SEVEN: DISSERTATION STUDY TWO: EFFECT OF IMMERSION AND AGENCY OF CONTROL ON EMBODIED EXPERIENCES……………..61 Methods………………………………………………………………………..64 Results………………………………………………………………………....71 Discussion……………………………………………………………………..76 CHAPTER EIGHT: CONCLUSION………………………………………………79 Summary of Findings………………………………………………………….79 Theoretical Implications – Embodied Cognition……………………………...80 Theoretical Implications – Immersion and Presence in Virtual Environments …………………………………………………………………………………84 Theoretical Implications – Environmental Studies……………………………86 Alternative Theoretical Explanations...…………………………….………….87 Applied Implications………………………………………………………….90 Limitations and Future Directions…………………………………………….92 NOTES……………………………………………………………………………..97 APPENDIX A: STIMULUS FOR MENTAL SIMULATION CONDITION IN STUDY 1…………………………………………………………………………..98 APPENDIX B: STUDY 1 SURVEY ITEMS...…………………………………..100 APPENDIX C: SURVEY ITEMS FOR STUDY 2……………………………….104 APPENDIX D: STATISTICS FOR ALL ANALYSES IN STUDY 1…………...108 APPENDIX E: MEANS AND STANDARD DEVIATIONS FOR ALL DEPENDENT VARIABLES IN STUDY 2………………………………………110 APPENDIX F: STATISTICS FOR ALL ANALYSES IN STUDY 2……...……120 REFERENCES……………………………………………………………………124 xii LIST OF TABLES Table 1. Study 1 Means and Standard Deviations for Dependent Variables by Condition…………………………………………………………………………...55 Table 2. Pearson Correlations between Dependent Variables in Study 1 (N = 47) ……………………………………………………………………………………...57 Table 3. 2x2 Between-Participants Design for Study 2……………………………66 Table 4. Pearson Correlations between Dependent Variables in Study 2 (N = 101) ……………………………………………………………………………………...75 xiii LIST OF FIGURES Figure 1. Experimental Setup for the IVE Condition in Study 1…………………..48 Figure 2. Screenshot of the Series of Events in the IVE Condition in Study 1……51 Figure 3. Experimental Setup for Low Immersion, Self-Move Condition in Study 2 ……………………………………………………………….……………………..67 Figure 4. Interaction between Agency of Control and Perspective Taking Propensity on Napkin Use in Study 2………………………………………………………….72 Figure 5. Interaction between Self-Efficacy and Perspective Taking Propensity Over Time in Study 2…………………………………………………………………….74 xiv CHAPTER ONE: INTRODUCTION Just as the Internet has significantly changed the way that we express ourselves and interact with others (Bargh & McKenna, 2004), the advancement of digital media such as video games and virtual environments continues to transform traditional communication rules. Researchers from various fields have discovered numerous benefits of applying state-of-the-art digital media to their work as research tools (Blascovich et al., 2002; Persky & McBride, 2009). Using digital technology, scholars are able to obtain reliable measurements of human behavior that are accurate to the millisecond and millimeter while maintaining a balance between ecological validity and experimental control which has long plagued empirical scientists as a shortcoming of laboratory research. In addition, novel affordances of digital media give rise to unique approaches and solutions to research themes of the past that could not be answered with traditional methods, due to the lack of technical capacity needed to approach such an issue. This dissertation explores how advanced digital technology can augment human sensory capacities (e.g., Bailenson, Beall, Blascovich, Loomis, & Turk, 2005) and how digitally enhanced multisensory experiences can influence attitudes and behaviors that transfer to the non-mediated, physical world. Furthermore, unique affordances of these advanced digital media are parsed out and investigated to gain deeper understanding of the underlying mechanisms of digitally augmented experiences. The capacity to digitally augment sensory experiences allows advanced digital technology to offer embodied experiences – a vivid, realistic mediated experience bolstered by simulated sensory information. Mediated experiences were available with more traditional media such as books and television (Reeves & Nass, 1 1996) but novel affordances of advanced digital media allow users to go beyond passive viewership and become active participants in the mediated context, seeing, hearing, and feeling the experience as if it were their own. The questions of interest in this dissertation are how active participation in the mediated experience compares to the more passive interactions with traditional media and the specific elements of advanced digital media that influence user attitudes and behaviors. Immersion is the main novel affordance that enables digital media to reproduce realistic and vivid embodied experiences. Conceptually, immersion refers to users being surrounded or enveloped by sensory information simulated by digital devices that allow them to temporarily forget the fact that they are in a mediated environment, causing them to think and behave as if they are in the real, physical world (Heeter, 1992; Slater, Usoh, & Steed, 1994; Steuer, 1995). Immersion is one of the affordances that differentiate advanced digital media from traditional ones in that they are able to mimic the real world and face-to-face interactions with more realism than any other traditional medium to date (Grigorovici, 2003). The realism of embodied experiences is important because the theory of embodied cognition stipulates that our mind is defined by the limitations of our body and our specific situation or environment (Clark, 2001; Gallagher, 2005). If we learn and think via the experiences involving our body, then the simulated experience becomes similar to experiences in the non-mediated, physical world. The advantage of using advanced digital media to explore embodied experiences is that there is almost infinite flexibility in terms of the mediated context constructed for these simulated experiences. Thus, users are able to actively participate in experiences that they were only able to imagine with traditional media, while receiving vivid, tangible sensory inputs. This makes it possible for scholars to 2 answer innovative and perhaps radical questions with regard to how active experiences can influence the way individuals think and behave. Despite the promising potential for real life implications and benefits, surprisingly few empirical studies have looked at applying advanced digital media such as virtual environments to explore the processes and effects of embodied experiences. This dissertation aims to lay the cornerstones to study the use of virtual environments in embodied cognition research and the significance of immersion as a novel affordance of advanced digital media. The following chapters will 1) provide an overview of embodied cognition theory and introduce the concept of embodied experiences; 2) discuss functional characteristics of embodied experiences through digital media; 3) discuss subjective characteristics of embodied experiences through digital media; 4) present two new studies designed to compare embodied experiences against imagined experiences and how these modalities influence attitude and actual behaviors in the physical world; and 5) discuss theoretical and applied implications of embodied experiences using advanced digital media. 3 CHAPTER TWO: EMBODIED COGNITION AND EMBODIED EXPERIENCES The theory of embodied cognition can be distinguished from more traditional cognitive science in the emphasis it places on the role of the body – body being the biological component of self (versus the mind) – and the surrounding environment. Earlier cognitive theories thought of the cognitive process as analogous to a computer’s main processing unit, assuming that the mind is software that runs on brain hardware and cognition is a logical process based on pure computation. In comparison, the theory of embodied cognition focuses on the physical attributes of the body and interactions among the body, environment, and the mind (Shapiro, 2007; Wilson, 2002). For instance, when infants learn how to perform a simple action such as picking up an object, they do so through dynamic interactions with their environments and discover the best way to execute this action through trial and error rather than follow some innate, pre-programmed neural map inside their brains (Thelen & Smith, 1994). Neurological Evidence of Embodied Cognition Embodied cognition emphasizes intrinsic ties between the body’s action and cognitive processes (Feldman & Narayaman, 2004) and opposes the view that the mind moves the body through abstract and formal logic. The discovery of mirror neurons provides a biological explanation for this action-perception link. Mirror neuron activation was discovered in the premotor cortex of monkeys, exhibiting increased activity both when a monkey performed hand movements itself and when it merely observed another monkey or a human performing the same hand movements (Ferrari, Gallese, Rizzolatti, & Fogassi, 2003; Gallese, Fadiga, Fogassi, & Rizzolatti, 1996). Similar neuron activity was found in the human brain using functional neuroimaging studies (Grezes & Decety, 2001), implying that perception 4 is linked with action inside the brain. That is, once sensorimotor schemata that link the body and mind are constructed in our minds, merely perceiving or imagining another person in a situation activates neurons connected with the actual action. For instance, the same part of the brain became activated both by merely viewing pictures of disgusted faces and by actually smelling disgusting odors (Wicker et al., 2003). Mirror neuron activity was also triggered when only the sounds that a certain action produces were heard (Kohler et al., 2002). Further evidence has been found by Rizzolatti and colleagues (Di Pellegrino, Fadiga, Fogassi, Gallese, & Rizzolatti, 1992) with the discovery of canonical neurons in the rear section of the arcuate sulcus. Canonical neurons respond selectively to three-dimensional objects, differentiating them in function of their shape, size, and spatial orientation. For example, if an object is large enough for an individual to use his or her whole hand to grasp it (versus using just fingers), mere observation of an object of similar size will activate the same canonical neurons. However, these neurons will not activate upon observation of a smaller, different sized object. It should be noted that these neurons will be activated not only in response to observing same object that the individual has interacted with, but with objects that require similar interactions. The activation patterns of these neurons indicate that once sensorimotor schemata are constructed, mere perception of related objects or movements activate relevant neuron systems. Thus, once the body learns how to interact in a certain way with the environment, observation of objects with similar characteristics automatically evokes the most suitable motor program required to interact with the environment (Gallese, 2000). This process of simulation is what mediates the relationship between action and perception (Lakoff & Johnson, 1999), and 5 neurological evidence confirms that simulation is not based on logic and reason but on sensorimotor experiences. Behavior Evidence of Embodied Cognition Behavioral evidence of the body influencing how individuals think and feel can also be found. Objects and events that produce similar affective responses are remembered together in the same perceptual category (Niedenthal, Halberstadt, & Innes-Ker, 1999), and these perceptual inputs are later used as bases in future judgments (Barsalou, 1999). More recent studies showed that individuals primed with either hot or cold tactile temperatures by holding hot or cold drinks before meeting another person would later judge that person to have a warm or cold personality, respectively. The same manipulation also led individuals to behave in a prosocial or egocentric manner, respectively (Williams & Bargh, 2008). Participants in both studies demonstrated no awareness of the impact of the physical experience on their judgment. Thus, tactile experiences of physical warmth or coldness are able to directly influence the way people think, feel, and behave even when they are unconscious of this influence. Similarly, the sensory experience of feeling the relative weight of objects can affect judgments. When holding a heavy clipboard, participants assessed foreign currency as more valuable compared to those holding a lighter clipboard (Jostmann, Lakens, & Schubert, 2009). Also, the perception of darkness created by wearing sunglasses (as opposed to clear glasses), has been shown to increase the perception of anonymity, leading to increases in morally questionable actions such as cheating (Zhong, Bhons, & Gino, 2010). If the above studies demonstrated the link between sensory perception and cognition, other studies evidenced the connection between motor perception and cognition. People are likely to agree with statements when they make nodding head 6 movements while listening (Wells & Petty, 1980); rate a cartoon as humorous when their facial muscles used for smiling are stimulated unobtrusively as they view the cartoon (Strack, Martin, & Stepper, 1988); feel pride in an achievement when sitting upright than slumped as they hear news about their performance (Stepper & Strack, 1993); and find a random pair of letters likeable if they have extensive experience typing and the letter pair is easy to type (Beilock & Holt, 2007). Body movements have also been shown to influence higher order cognition, such as solving complex physics problems. When participants were asked to solve a physics problem and either asked to make arm movements relevant to the solution or irrelevant to the solution, those who made relevant arm movements were significantly more successful at solving the problem even when they were unaware that the arm movements were relevant to the solution (Thomas & Lleras, 2009). Thus, leading individuals to move in a particular way can influence the processes of the mind. On the other hand, limiting motor perceptions can also restrict the processes of the mind. In a recent study, when facial muscles used in frowning were paralyzed with Botox injections, participants took a significantly longer time to read sentences evoking anger that would trigger frowning muscles compared to reading sentences that evoke sadness or happiness (Havas, Glenberg, Gutowski, Lucarelli, & Davidson, 2010). It should be noted that the action-perception link demonstrated in these studies are different from behavioral modeling such as that of social cognitive theory (Bandura, 1977), which stipulates that people can learn behaviors vicariously through observation of models. Rather, the sensorimotor experience – nodding, holding a warm drink – seem to trigger the sensorimotor schema related to the experience in some way – perception of agreement, perception of kindness. Due to 7 the relatively short history of research on embodied cognition, the exact underlying mechanism that links the sensorimotor experience to relevant sensorimotor schema is not entirely clear. However, neurological and behavioral evidence discussed above demonstrate that humans have the ability to categorize mental schema into relevant groups, and a sensorimotor experience can trigger any relevant schema categorized into the same group. This is why individuals relate the experience of visual darkness to anonymity and immoral actions, and how they link physical warmness to warm personalities although the sensorimotor experience does not necessarily connect directly with the triggered schema. Mental Simulation As discussed above, once sensorimotor schemata are created, even the mere observation of related objects, events, and people activate neurons involved with the action. Upon observation, relevant neural systems are activated as if the observer were interacting with it. This virtual, or “off-line,” simulation of potential action is known as mental simulation (Goldman, 1989). Because of this link between mental simulation and action neurons, mental simulation techniques are commonly used to develop athletic skills (Hausenblas, Hall, Rodgers, & Munroe, 1999) as well as promote task self-efficacy and enhance skill performance (Cumming, 2008; Martin & Hall, 1995). Several studies have explored the effect of mental simulation on attitude and behavior change to demonstrate that simple imagination is able to trigger perceptual simulation of the senses based on previously constructed sensorimotor schema. For instance, participants who recalled a past experience of social rejection perceived the room’s temperature as significantly lower than participants who recalled experiences of social inclusion (Zhong & Leonardelli, 2008). Similarly, 8 retrospective thinking about life in the past triggered participants to lean backwards whereas prospective thinking about life in the future triggered them to lean forward (Miles, Nind, & Macrae, 2010). A series of other studies show that text stimuli are able to induce mental simulation that leads to activation of sensorimotor schema. When reading verbs related to either positive or negative emotions (e.g., to smile, to frown), facial muscles associated with positive or negative expressions were stimulated (Foroni & Semin, 2009). The connection between text-induced mental simulation and the activation of sensorimotor schema is further supported by neurological evidence from right- and left-handed individuals. When reading verbs related to manual action (e.g., grasp or throw), the area of the brain that is triggered during actual motor activity for right- and left-handed individuals became active, respectively (Willems, Hagoort, & Casasanto, 2009). A related neurological study demonstrated that individuals understand a story by mentally simulating different events in the narrative (Speer, Reynolds, Swallow, & Zacks, 2009). Virtual Environments and Embodied Experiences The fact that people’s thoughts and feelings are limited by their body’s physical capacities seems to be a big constraint of embodied cognition (Glenberg, 1999). That is, human action and thoughts are bound by the affordances of the human body, such as body type, perceptual apparatus, and means of interaction with the environment. For instance, a human being has completely different means of playing with a ball compared to a puppy and thus constructs very different sensorimotor schema that link actions with cognitions. Mental simulation would also be bound by this restriction even if it is based on imagination – without a previously constructed sensorimotor schema, there would be no basis to guide the 9 simulation. This implies that simulating a situation that is beyond the capacities of the human body or that the individual has no prior experiences may be difficult to process. Virtual environments offer unique solutions so that individuals may go beyond the constraints of the body or of prior experiences. At the click of a button, users are able to change their self-representation at will to any type or form of body, sex, or species and experience the virtual world embodying a virtual representation completely different from the physical one in the real world. Furthermore, virtual environments are able to augment the sensory capacities of the human body, for instance, by allowing users to simultaneously expand their gaze to different people or to be present at two different places at the same time (Bailenson, Yee, Blascovich, & Guadagno, 2008). Although more traditional media such as television, film, and video have been able to extend the capacities of human sensory systems to some degree (e.g., show the world from another person’s point of view, present fantastical characters that viewers can mentally embody), virtual environments offer novel affordances that maximize the experience of embodiment. In this dissertation, embodied experiences are defined as the users’ experiences within virtual environments with vivid visual, aural, and haptic sensorimotor inputs and the ability to actively interact with the mediated environment, such as with objects and people. These are experiences in which users are able to embody a completely different body and see, hear, and feel completely novel situations that transcend physical space and time. Such experiences have not been possible with traditional media and present immense potential to gain deeper insight into the processes of the body and mind by asking questions that have been difficult to address until recently. Embodied 10 experiences in virtual environments are as close as one can get to physical experiences using mediated content (Grigorovici, 2003), but they are still virtually mediated experiences. Thus, the question of interest is whether sensorimotor experiences in virtual worlds are able to influence attitudes and behaviors in the physical world. Also of interest is how embodied experiences compare to mental simulation of the same experience when individuals lack a prior constructed sensorimotor schema. To better understand the characteristics and affordances of virtual environments and embodied experiences, a discussion of functional and subjective features of virtual environments that make embodied experiences possible is in order. 11 CHAPTER THREE: FUNCTIONAL FEATURES OF EMBODIED EXPERIENCES IN VIRTUAL ENVIRONMENTS Virtual environments are realistic artifacts simulated by digital computers, devices, and their associated technologies that blur the distinction between reality and its virtual representation (Ellis, 1995). There are several functional features of virtual environments that set them apart from traditional media in terms of providing embodied experiences. These affordances augment sensorimotor inputs and aid in creating experiences that are realistic enough for the user to respond as if he or she is in a non-mediated, physical environment. Immersion Immersion is a concept often used to describe a novel affordance of digital media which serves to heighten the reality of the mediated content. Slater and Wilbur (1997) define immersion as the extent to which media are capable of delivering an inclusive, extensive, surrounding, and vivid illusion of reality to the senses. Singer and Witmer (1999) describe immersion as an individual’s perception and reaction to a virtual environment. Murray (1997) suggests a more metaphorical definition of immersion: “Immersion is a metaphorical term derived from the physical experience of being submerged in water. We seek the same feeling from a psychologically immersive experience that we do from a plunge in the ocean or a swimming pool; the sensation of being surrounded by a completely other reality… that takes over all of our attention, our whole perceptual apparatus…” (p. 98-99). Although the field has not been able to settle on a canonical definition yet, taken together, the concept of immersion describes how users are surrounded by layers of sensory information simulated by advanced digital technology that create the illusion of being in the physical world. 12 Virtual environments can differ in the level of immersion that they offer. Immersive virtual environments (IVEs) are virtual environment systems that amplify the effect of simulation by surrounding the user with numerous layers of sensory and perceptual information created by digital devices (Loomis, Blascovich, & Beall, 1999). The more sensory information is provided, the higher the level of immersion that the IVE offers. IVEs are able to surround users with stereoscopic visual input, spatialized aural input, and tactile sensory input, yielding a sense of perceptual depth and vivid realism to the virtual world. For instance, by building a simulator which represents all the sensory perceptions experienced by a schizophrenic, an ordinary person is able embody the realistic perceptual experiences of this mental disability (Kalyanaraman, Penn, Ivory, & Judge, 2010). In comparison, virtual environments with lower levels of immersion such as desktop computers offer monoscopic visual, simple audio, and limited tactile sensory input. IVEs can be implemented in different ways (see Loomis, Blascovich, & Beall, 1999 for details). The IVE system used for this dissertation was comprised of the head-mounted display (HMD), a headpiece with a lens for each eye which provides stereoscopic views of the computer-generated environment, and various devices that track simple head and body movements as well as the position of the body in three-dimensional space. Spatialized sound from headphones built into the HMD allowed users to hear sounds that seemed to be emanating from surrounding auditory space (Wenzel, 1992). A force feedback haptic device was applied to yield tactile stimulation of arm and hand movement and interaction with the virtual environment. Several studies have explored how the scope and range of sensorimotor 13 inputs provided by the virtual environment system can influence users’ attitudes and behaviors. One of the earliest efforts to quantify the levels of immersion of different devices compared head-controlled point of view against hand controlled point of view in a search task and found that users with head-controlled point of view spent substantially less time compared to those with hand controlled point of view (Pausch, Proffitt, & Williams, 1997). Other studies have also compared higher (i.e., IVEs) and lower (i.e., desktop computers) immersive virtual environment systems and confirmed significant benefits of IVEs in terms of data visualization and processing (Arns, Cook, & Cruz-Neira, 1999; Raja, Bowman, Lucas, & North, 2005); performance on a path construction task (Gruchalla, 2004); search and navigation task (Boyd, 1997); depth and distance perception (Heineken & Schulte, 2000); collaboration task involving close interaction with a remote user (Roberts, Wolff, & Otto, 2005); configuration and movement of chess pieces (Slater, Lanikis, Usoh, & Kooper, 1996); and short-term spatial memory when a navigation task is involved (Johnson & Adamo-Villani, 2010). For example, various levels of immersion in a virtual environment were found to be more effective in terms of directional accuracy and precision locating an unfamiliar landmark compared to static images on paper or paper and pencil drawings (Waller, Beall, & Loomis, 2004). Some studies report no significant differences between high and low immersive environments. In a virtual search and navigation task presented in either HMD or desktop, Slater and colleagues (1995) failed to find significant differences between the two presentation modes. A pilot study (Wiederhold, Davis, & Wiederhold, 1998) observed responses from five participants after presenting a virtual airplane ride through a HMD or a 3D-monitor but found no differences in 14 physiological responses such as heart rate, skin temperature, and respiration rate between the two presentation modes. Despite some inconsistent findings, these studies generally imply that higher IVEs which provide more numerous layers of perceptual inputs may be more effective than lower IVEs, particularly for sensorimotor tasks. For the dissertation studies, it is anticipated that virtual environments which provide higher levels of immersion through rich layers of perceptual input will construct more influential embodied experiences compared to lower immersive stimuli. As a result, embodied experiences offered via high IVEs will be more likely than lower IVEs to alter attitudes and behaviors in the non-mediated physical world. Interactivity Interactivity is another characteristic of virtual environments that provide sensorimotor experiences, and is defined as the process in which the user can influence the form and/or content of the mediated experience (Heeter, 2000; Lombard & Ditton, 1997); the user’s perception that the medium is responding to the user’s actions (Leiner & Quiring, 2008; Steuer, 1995); and the medium’s technological capacity to actually respond (Lee, Park, & Jin, 2006) in a two-way exchange, immediately, in real-time (Rice & Williams, 1984). It is generally agreed that the best interactive medium mimics the interactive dynamics of face-to-face communication (Rafaeli, 1988). While interactivity is not a characteristic unique to virtual environments, virtual environments tend to provide users with the most engaging and responsive stimuli that respond in real-time to user actions. Interactivity allows the user to be both an observer and a participant in mediated environments, possibly leading to more potent media effects (Vorderer, 2000). Virtual environments offer interactivity in several ways that encourage 15 greater user control, participation, and engagement (Sundar, Xu, & Bellur, 2010). On websites, input and output features built into the medium such as scroll bars, hyperlinks, or movie clips keep many sensory channels involved during an interaction between media and their users. Tailored content that offer enhanced personalization over time based on user inputs (e.g., news feeds, avatar creation in video games) allows users to become not just passive receivers, but the source and the sender during the communication process. In IVEs, interactivity allows users to move in the virtual environment as if they were in a non-mediated, physical world and the objects and people within the IVE aim to respond to users as they would in the real world. There are various benefits of higher interactivity (compared to lower interactivity) such as better product knowledge and positive brand attitudes after exposure to online advertisements (Ahn & Bailenson, in press; Li, Daugherty, & Biocca, 2002), higher audience involvement compared to traditional media (Fortin & Dholakia, 2005), greater perception of reality (Biocca et al., 2001; Edwards & Gangadharbatla, 2001; Li, Daugherty, & Biocca, 2001; Lombard & Ditton, 1997; Skalski & Tamborini, 2007), and more positive attitude or liking toward the mediated content (Sundar & Kim, 2005). On the other hand, multi-sensory stimuli that offer immediate feedback and response to user inputs may incur unforeseen costs such as cognitive overload. Presenting individuals with highly interactive advertisements with animation features degraded product memory although it increased recognition of the advertisement (Sundar & Kim, 2005). Other studies demonstrate that although users like audio and video features of a website, they learn more through the least interactive modality in the form of text and static pictures (Sundar, 2000). Contrary 16 to what intuition might suggest, more interactive features is not necessarily better. Although these features might capture the users’ attention or interest, it is also highly likely that numerous interactive features will tax their cognitive resources. Thus, a timely investigation of the effect of interactivity presented in virtual environments – especially when coupled with immersion – on user perceptions of embodied experiences as well as its effects on people’s attitude and behavior in real life is imperative. Interactivity features presented in IVEs are based on naturalistic tracking of movements and gestures and may be more intuitive compared to virtual environments that are lower in immersion, such as websites. That is, interactive features within IVEs such as head-controlled point of view and haptic feedback are designed to mimic real perceptions from the physical world. Thus, much of the interactive features presented in high IVEs rely on existing sensorimotor schemata. To this extent, it is anticipated that even with highly interactive features, embodied experiences within IVEs will not place a burden on the users’ cognitive load. Combination of Flexibility, Control, and Realism Another important functional feature of virtual environments that would be appealing for scholars studying embodied experiences is that the flexibility of the context of the experience is almost limitless. Within virtual environments, users have the freedom to embody any type of body and be inside any type of environment. The flexibility of body type is made possible through the use of avatars, a form of virtual self-representation that the user is able to control within the virtual environment (Ahn, Fox, & Bailenson, in press). The flexibility of environment type is made possible through the flexible nature of computer graphics that allow users to render realistic representations of the physical world. The distinctive advantage of virtual environments is that in addition to this flexibility, 17 individuals have vivid and tangible sensorimotor experiences with high immersion and interactivity as if they were in a non-mediated, physical world. A clear example of this balance between flexibility and high realism is Lanier’s concept of homuncular flexibility (2006). The homunculus is the mapping of the body into the motor cortex. The notion of its flexibility posits that humans are able to embody virtual self representations that have completely different body parts with limbs they have never used before. Lanier’s example of homuncular flexibility draws upon embodying a virtual lobster with more than two arms and two legs. Despite the lack of previously constructed sensorimotor schemata on how to move the extra six limbs, some practice within interactive IVEs can help humans learn to adapt to their virtual body parts. The concept of this “homuncular lobster” implies that embodied experiences within IVE are able to expand the human mind to construct completely novel sensorimotor schemata and connect those schemata to completely novel body parts. In essence, IVEs allow users to experience a literal translation of “stepping into the skin” of another being, and high immersion and high interactivity make this embodied experience sufficiently natural and realistic for individuals to respond as if the embodied experience were occurring in the real world. A series of experiments demonstrated IVEs’ capacity to allow individuals to virtually step into another person’s body and experience the world through that person’s eyes to explore the effect of embodiment on their attitude and behavior. By embodying the body of an elderly avatar in an IVE, participants demonstrated a decrease in negative stereotypes against elderly individuals (Yee & Bailenson, 2006). When participants embodied an attractive avatar, they were more willing to stand closer to an unfamiliar person and disclose more information about the self 18 compared to those who embodied less attractive avatars (Yee & Bailenson, 2007). In the same paper, participants who were assigned taller avatars negotiated more aggressively than those who were given shorter avatars on a negotiation task. In a follow-up study, Yee and colleagues (2009) demonstrated that the effect of embodying tall or short avatars in the virtual world could transfer into the physical world, where participants who embodied taller avatars negotiated more aggressively than those who embodied shorter avatars. Groom and colleagues (2009) had participants embody either an African-American or a White Caucasian avatar in the virtual world and asked them to “imagine a day in the life of this individual as if you were that person.” They demonstrated that the experience of virtually embodying another person’s body was able to influence people’s attitude about racial bias (through stereotype activation) whereas mentally simulating the embodiment failed to do so. IVE also allows users extensive control of the mediated environment in that they can easily recreate any type of environment as needed, transcending spatial restrictions. At the touch of a button, users can stand in a classroom or be on an island, with vivid visual, aural, and tactile sensory inputs from each environment as well as the ability to interact with the objects in the environment. Also, just like other advanced digital media such as video, IVEs are also able to accurately replicate and reproduce the same stimuli almost infinitely and users can experience the same experience time and time again. Experimenters can benefit from IVE’s capacity for extensive control in that they are able to unobtrusively track and measure every movement that the user makes in the virtual environment. Thus, they have begun to view IVEs as optimal solutions for exercising experimental control and obtaining accurate measurements 19 while retaining mundane realism in the laboratory (Blascovich et al., 2002). Numerous researchers have used IVEs to explore and replicate traditional social psychological theories. Among many others, interpersonal distance (Bailenson, Blascovich, Beall, & Loomis, 2003), social facilitation (Hoyt, Blascovich, & Swinth, 2003), and prejudice (Dotsch & Wigboldus, 2008) theories studied in the physical world have been replicated successfully within IVEs. In health contexts, Persky and McBride (2009) noted the significant potential of IVEs to be integrated into medical training and services by having clinicians embody the viewpoint of their patients to experience and evaluate their own counseling technique. Furthermore, disabilities such as schizophrenia (Kalyanaraman, Penn, Ivory, & Judge, 2010) and various visual disabilities (Jin, Ai, & Rasmussen, 2005) have been accurately reproduced as virtual simulations. Although the technology is far from perfect and even IVEs with the highest degree of immersion are still unable to completely mimic the real world, these studies confirm that IVE technology can invoke naturalistic responses from participants while maintaining extensive experimental control. In sum, IVEs provide a novel approach for the embodied cognition research program by allowing individuals to virtually embody an avatar of any type or form in any sort of environment. During the experience, users are surrounded by rich layers of sensory inputs to see, hear, and touch objects in a three-dimensional space that responds in real time to user inputs. Compared to traditional media or mental simulation, this is a much more tangible and interactive form of embodied cognition particularly when the individual has no prior constructed sensorimotor schema on the particular body type (i.e., embodying an elderly person) or the environment (i.e., living in a foreign country). Details of the embodied experience may be tailored to the individual, for instance, sensory inputs that are programmed to the millimeter 20 and millisecond to control exactly what the user sees, hears, and feels. Thus, IVEs offer an optimal combination of flexibility, control, and realism, potentially making them attractive tools to explore questions of embodied cognition. 21 CHAPTER FOUR: SUBJECTIVE FEATURES OF EMBODIED EXPERIENCES IN VIRTUAL ENVIRONMENTS Given that the ultimate goal of all media is to reproduce the illusion of nonmediated communication as best as they can, the degree of vividness or realism that users experience during their experiences within virtual environments will influence their attitudes and behaviors. Presence is the psychological state of feeling that the mediated experience reproduced by virtual environments is “real.” The term telepresence, which preceded the widespread use of “presence” as a more generalized application of the concept, was first coined by Marvin Minsky (1980) to refer to the sense of being physically present at a remote location through interaction with a system’s interface. Biocca (1997) went on to refine the definition of presence, referring to it as the illusion of “being there” regardless of whether “there” is physical, mediated, or imagined. Lombard and Ditton (1997) presented a similar definition of presence as the perceptual illusion of nonmediation, meaning that although individuals can later indicate that they were using the technology, their subjective perceptions make it seem as if the technology was not involved in the experience (Lombard, 2001). Some scholars have used immersion and presence interchangeably because of their obvious conceptual similarities. In this dissertation, the two concepts will be distinguished by defining presence as the subjective unit of evaluating the realism of the mediated experience, whereas immersion would be the objective, or technological unit of evaluation. That is, even when users are exposed to the same mediated environment (i.e., immersion), individuals may have different subjective assessments of how realistic it is (i.e., presence). Immersion will be operationalized by manipulating the components and layers of sensory inputs provided by digital 22 technology while presence will be measured as various forms of individual assessments of the virtual environment’s realism. Because presence is an entirely subjective experience of reality while exposed to mediated content, users’ perception of presence is bound to change over time and the advent of sophisticated technology. For example, when the Lumiere brothers introduced the first motion picture in 1895 of a train approaching a station, it had people screaming and running for cover. Obviously, the audience back then felt a high sense of presence while viewing the movie. However, two-dimensional black and white films are no longer able to elicit such high levels of presence among today’s audience as their reception and understanding of mediated content have become more sophisticated over time (Campbell, 2000). As a result, it is expected that relatively newer forms of media which offer richer sensory inputs will be more successful in terms of creating realistic illusions of “being there.” Green and colleagues (2004) also note that newer forms of digital media such as video games or virtual reality simulation are particularly more likely to result in high presence compared to traditional media. The vivid sense of “being there” created through perception of presence offers users with experiences realistic enough to lead to persuasion and attitudinal changes. For instance, consumers with high perception of presence were more likely to be persuaded by a television advertisement compared to those who felt less presence (Kim & Biocca, 1997). In their study, this difference was driven by the subjective experience of presence alone and the manipulation of immersion (i.e., angle of viewing, lighting) did not affect results. A study exploring video game research found that IVE and desktop platforms induced different levels of presence, and the perception of presence mediated the likelihood to develop aggressive 23 feelings after playing a violent video game – high presence led to more aggressive feelings (Persky & Blascovich, 2008). In the realm of health research, high levels of perceived presence induced by an interactive computer agent led individuals to react favorably to the agent when the agent was attractive and even reduced negativity when the agent was unattractive. Furthermore, when perceived presence was high (i.e., higher interactivity), individuals were more likely to be persuaded by health messages compared to when perceived presence was low (Skalski & Tamborini, 2007). Similarly, high perception of presence elicited by interactive selfrepresentations led to changes in eating behaviors (Fox, Bailenson, & Binney, 2009). Studies investigating task performances have found that high levels of perceived presence are also positively linked with task performance (Sas, O’Hare, & Reilly, 2004; Slater, Linakis, Usoh, & Kooper, 1996). These studies imply that the subjective perception of presence may be the underlying mechanism driving the success of navigation and task performance within virtual worlds. Another implication is that greater perception of presence during the embodied experience may lead to important influences on users’ attitude and behavior in the non-mediated, physical world. Intuitively, because embodied cognition theory stipulates the connection between sensorimotor experiences of the body and the mind, it is likely that this relationship would be stronger if the user perceives the sensorimotor experience in the virtual world to be more realistic. Indeed, studies have demonstrated that when the sensory experience is sufficiently realistic, the person feels an illusion of the physical body merging with the body of the self representation in the virtual environment (Sanches-Vives, Spanlang, Frisoli, Bergamasco, & Slater, 2010; Slater, Spanlang, Sanches-Vives, & Blanke, 2010). In one of these studies, Sanches-Vives and colleagues demonstrated that by 24 synchronizing the haptic sensation of moving the physical hand and the hand of the self avatar for approximately 2-3 minutes, participants later felt the sensation of their stationary physical arm moving when they saw the virtual arm move. This sense of embodiment elicited by perceived realism is a literal translation of ‘stepping into’ another person’s shoes and thus, presence may be the key to understanding the processes of embodied experiences. There is still much to be learned about presence and scholars are still in the process of developing and refining the conceptual framework. Although there is general agreement that presence should be considered a combination of several dimensions rather than a single construct, scholars have yet to agree upon a fixed set of components and their relationship with each other. This has led to a myriad of confusing labels and names coined by different scholars, but there seems to be largely three dimensions that are explored when investigating the concept of presence: self, social, and spatial. Self presence refers to the psychological state in which the user feels that the actual self is experiencing what the virtual self is experiencing, or a strong connection between the virtual representation of the self and the actual self (Biocca, 1997; Lee, 2004). Social presence can be defined as the feeling of being with another being or individual in the mediated space (Biocca, Harms, & Burgoon, 2003). Lastly, spatial presence is the degree to which the user feels that the mediated environment and the objects within the environment that surrounds him or her is real to the extent that the environment responds realistically to user inputs (Biocca, 1997; Heeter, 1992). Another consequence of being a relatively new concept explored in a new medium is that scholars have yet to concur on a validated and widely used measure of presence, despite their agreement on its importance. Most studies use self-report 25 questionnaires to gauge presence, and there is a wide array of different questionnaires that are being used by different researchers (e.g., Biocca, Kim, & Choi, 2001; Lessiter, Freeman, Keogh, & Davidoff, 2001; Witmer & Singer, 1998) that define and measure presence in slightly varying ways. Not only does the scattered use of different self-reports fail to help foster validity, but participants may also not understand if novel terms and technical jargon are used in the questionnaire items, leading to inaccurate responses (Slater, 2004). Although used less frequently than self-reports, there are more objective options of measuring presence, such as gauging physiological measures like heart rate and skin conductance (Meehan, Razzaque, Whitton, & Brooks, 2003) or assessing behavioral responses such as walking behavior (Usoh et al., 1999), startle response (Slater & Usoh, 1993), reflex reactions (i.e., avoiding a vehicle heading towards you; Loomis, 1992) to see how closely participants’ responses to mediated stimuli match those presented in the real world. Recall measures have also been used as an inverse proxy measure of presence (Fox, Bailenson, & Binney, 2009; Nichols, Haldane, & Wilson, 2000) under the assumption that when users are intensely engaged in an experience, they are likely to pay less attention to and remember less of the information given during the engaging experience due to limited cognitive capacity. Although more objective than self-reports, these measures may be limited in that they are not direct measures of presence, but rather, assume that changes in physiological and behavioral responses are in some way connected to the perception of presence. Consequently, using a combination of both subjective and objective measures to evaluate presence would complement the shortcomings of each measure (Bailenson et al., 2004) and both types of measures will be applied in the current dissertation. 26 Individual Differences in Presence Perception Presence is a subjective state. As a result, different individuals may pay attention to totally different stimuli and may feel different levels of presence even if they are sharing the same mediated environment. Heeter (2003) argues that the particular sensory stimuli that an individual might notice and pay attention to may depend on individual differences such as personality, past experiences, or the capacity for imagination. Steuer (1992) also proposed that the capability to feel presence would depend on the interaction between individual factors and technological variables. Lombard and Ditton (1997) pointed out that an individual’s willingness to temporarily forget that he or she is in a mediated environment would influence the level of perceived presence. Waterworth and Waterworth (2006) and Wirth et al. (2007) suggested that individual differences in openness to experience emotional and cognitive alterations and vivid imagination would be an important predictor of presence, and Sas and O’Hare (2003) made similar predictions, suggesting that individual differences in imaginative skills would be a key predictor of presence. Thus, many scholars agree that individual differences can be major sources of variation in the perception of presence as well as attitudes and behaviors within virtual environments. However, empirical evidence investigating the influence of individual factors on presence is scarce and the few studies that have explored individual differences yield inconclusive results. One of the earliest attempts to empirically test the effects of personality factors on presence was conducted by Witmer and Singer (1998). They measured individual dispositions to feel presence using the Immersive Tendency Questionnaire, which is a scale they developed to assess individual likelihood to feel involved or engaged in common activities (e.g., How 27 frequently do you get emotionally involved – angry, sad, or happy – in the news stories that you read or hear?) and found positive correlations between the Immersive Tendency Questionnaire and presence measured with a separate Presence Questionnaire. Sas and O’Hare (2003; Sas, 2004) conducted the most extensive series of experiments investigating the role of personality factors on the perception of presence. They measured individual differences in empathy (willingness to share another person’s experiences; Davis’ Interpersonal Reactivity Index, 1983), absorption (openness to experiencing experiential events that are sensorial or imaginal; Tellegen Absorption Scale, 1982), creative imagination (ability to generate mental representation of objects, persons, or events not immediately presented to the senses; Barber and Wilson’s Creative Imagination Scale, 1979), and willingness to be transported (willingness to suspend disbelief to enjoy a mediated experience of any kind). Results confirmed that individuals who have higher dispositions for empathy, absorption, creative imagination and willingness to be transported experienced significantly higher levels of presence than those lower on these traits. On the other hand, Murray, Fox, and Pettifer (2007) presented a study measuring individual differences in absorption, dissociation (temporary disruption in consciousness or perception of the environment; Bernstein & Putnam, 1986), immersive tendency, and locus of control (degree to which people feel that they are in control of a certain event; Rotter, 1954). Results confirmed positive correlations between dissociation and locus of control with presence, but non-significant correlations between absorption and immersive tendencies with presence. The non-significant relationship between absorption and presence contradicts earlier findings, but this may be due to the fact that the two studies used different scales to measure presence. Sporadic and inconsistent use of 28 various self-report measures of presence has been a recurring problem in this field and this is why both self-report and objective measurements of presence will be used in the current dissertation in an effort to offset the shortcomings of each method. The most recent study on personality factors and presence (Wallach, Safir, & Samana, 2010) examined five of the individual differences mentioned above – empathy (measured with Interpersonal Reactivity Index), imagination (measured with Betts’ Questionnaire upon Mental Imagery; Sheehan, 1967), immersive tendencies (measured with Immersive Tendency Questionnaire), dissociation tendencies (measured with Dissociative Experiences Scale), and locus of control (Locus of Control Questionnaire). Using an IVE setup similar to the one used in the current dissertation studies with a HMD, participants experienced a virtual simulation of an airplane ride for ten minutes. Results demonstrated that empathy and an internal locus of control were the best predictors for the sense of presence that participants felt during the virtual plane ride. The current dissertation aims to advance these results by exploring individual dispositions to understand others’ experiences and the perception of control during embodied experiences. Based on the evidence from earlier studies, these individual differences are expected to moderate the level of perceived presence. Presence, in turn, is expected to be the underlying mechanism driving attitude and behavior changes following embodied experiences. Presence Perception in Different Modalities Presence is often discussed in the context of virtual environments, but scholars have argued that the illusion of “being there” may also be elicited by text (Gerrig, 1993), television (Bracken, 2005), and by narratives presented via any form 29 of media (Green, Brock, & Kaufman, 2004). In television or video, popular mainstream films such as The Blair Witch Project and Cloverfield have adopted a technique that shows a first-person perspective of the story under the premise that the protagonist is recording the entire film using a handheld camcorder. The firstperson perspective presentation amplifies dramatic tension because the audience is able to see and hear the narrative through the protagonist’s eyes and ears. While vividly sharing ‘in the moment’ perceptual experiences, the audience feels as though they are standing in the shoes of the protagonist, allowing them to momentarily disregard that the sensory content is being mediated through video and to feel a heightened sense of realism. Heightened presence from first-person perspectives in video also improves their learning and training. Lindgren (2009) demonstrated that when using video technology to assist observational learning, the first-person perspective (i.e., recorded by mounting a camera on the head of the person performing the task) is more effective in learning facilitation than video recorded in the third-person perspective (i.e., recorded by setting the camera up on a tripod). Participants who learned how to assemble a toaster based on a video taken in first-person perspective learned the assembly process in greater detail, remembered the process better, and performed better on inference questions based on the learned material compared to participants who saw the assembly process in the third-person perspective. In another similar study (Lozano, Hard, & Tversky, 2007), participants were shown a video clip of a person assembling a piece of furniture and told to verbally describe the process in either the first-person perspective or third-person perspective. Later, participants were asked to assemble the same piece of furniture. Those who had been instructed to describe the process in the first-person perspective made 30 significantly fewer errors. There is also contrasting evidence. In a study exploring video game playing and arousal (Lim & Reeves, 2009), participants showed no difference in physiological arousal based on first- or third-person visual perspective and a preference of the third-person perspective when the players were able to choose their own avatars. The author explains that this may be due to the design of the particular video game in that players in the first-person perspective were only able to see the environment and not their self-representation. Because they were unable to see their own avatars, players in the first-person perspective may not have perceived sufficient embodiment compared to players in the third-person perspective who had clear views of their avatar. Presence can also be perceived from text or narrative stimuli. When reading a narrative, individuals may feel completely immersed in the text and experience vivid mental images of settings and characters (termed narrative transportation; Green & Brock, 2000). Similar to the effect of presence perceived in virtual environments, greater perception of presence from narratives has been shown to lead to attitude change with individuals demonstrating more story-consistent beliefs and opinions than those who felt less presence (Green, Brock, & Kaufman, 2004). Even with text narratives, individual differences moderate the perception of presence. Individuals with cognitive styles that enjoy effortful cognitive activity felt higher presence in text compared to those with cognitive styles that tend to avoid cognitive effort (Green et al., 2008). Presence perception through text or narratives is essentially equivalent to engaging in mental simulation and has been used frequently as experimental stimuli in embodied cognition research. Upon reading the text or narrative, readers must cognitively simulate the hypothetical scenario in their minds to understand the story 31 and better enjoy the vicarious experience (Green, Brock, & Kaufman, 2004). The embodied cognition research contends that the mental simulation is based on previously constructed sensorimotor schemata, and perceptual neurons become activated at mere simulation of the action. This is how vivid mental simulation can seem as real to the individual as the physical experience. Studies have also confirmed that mental simulation can be triggered by having participants read text stimuli and the mental simulation leads to greater perceived presence. Perceived presence during the mental simulation, in turn, has positive effects on attitudes toward advertisements and brands (Escalas, 2004). Thus, presence is also hypothesized to be the underlying mechanism of mental simulation. In the current dissertation, embodied experiences presented with IVE will be compared to embodied experiences presented with mental simulation and presence perception in both modalities will be measured and assessed. 32 CHAPTER FIVE: JUSTIFICATION FOR DISSERTATION STUDIES Two studies will compare embodied experiences presented through IVE or mental simulation (MS). MS has been used as the main manipulation of interest to test embodied cognition in numerous studies under the premise that the body is linked with the mind. As discussed earlier, when previously formed sensorimotor schema is activated through MS, experiments demonstrated that mere imagination of an activity is powerful enough to change attitude and behavior of the body. The following dissertation studies aim to compare this traditional means of embodied experiences against embodied experiences within IVE in several aspects. Different Modalities and Embodied Experiences Relevant to the embodied cognition literature, mental simulation has been compared to physical activities in various sensorimotor contexts to confirm the connection between the brain areas that control mental simulation and actual sensorimotor activity. One of the earliest empirical evidence (Landauer, 1962) proved that it took participants almost the same time to either recite the alphabet out loud or to mentally simulate the recitation. Similarly, individuals took approximately the same time to write a short sentence either physically or mentally (Decety & Michel, 1989) and to walk towards targets placed at different distances either physically or mentally (Decety, Jeannerod, & Prablanc, 1989). However, when the task becomes difficult or awkward, for instance, moving the hand to an unfamiliar or awkward position, mental simulation takes much longer than physical activity and the correlation between the mind and the body becomes weak (Parsons, 1994). This implies that when individuals have no previously constructed sensorimotor schema to base mental simulations on (i.e., no prior experience) their simulations become either inaccurate or difficult to execute. 33 Embodied experiences presented via IVEs would overcome this limitation of mental simulation in that they offer maximal flexibility in terms of self representation and mediated environments. This flexibility is also bolstered with immersion which provides vivid sensory inputs, and interactivity which provides vivid motor inputs. Thus, for experiences that are novel or unfamiliar, IVEs are likely to provide a higher sense of presence during embodiment compared to MS. Only a few studies to date have compared embodied experiences within IVEs to MS. Fox (2010) compared IVEs to MS with the purpose of promoting health behaviors, asking participants to either watch their self representation perform pushups in an IVE or mentally simulate themselves performing pushups. There were no differences in behavioral outcomes between the two conditions, but female participants believed that they could perform significantly more pushups after watching themselves in IVE compared to MS. However, a limitation of this study is that participants in the IVE condition had no interactive control over their self representations and were only able to passively watch their virtual selves perform pushups. The fact that participants felt a higher sense of identification with the self in the MS than IVE condition confirms this speculation. Groom, Bailenson, and Nass (2009) had participants embody a self representation of either an AfricanAmerican or a White Caucasian in an IVE or mentally simulate the embodiment. Results indicated that embodied experiences via IVE are able to influence people’s attitudes about racial bias whereas MS failed to do so. Participants in this study were able to move their heads and walk inside the IVE to confirm the sense of embodiment but still had no sensorimotor task relevant to racial stereotypes, and thus cannot be considered a direct investigation of embodied experiences. More relevant to the current dissertation studies, I previously conducted 34 two studies to compare embodied experiences in IVE against MS. Red-green colorblindness, a visual disability that causes inability to perceive differences between red and green, was chosen as the context of embodiment. Only participants with normal color vision were recruited and embodying a colorblind individual was a novel experience for all participants. Following earlier studies, participants were divided into High and Low empathy groups using Davis’ Interpersonal Reactivity Index to determine whether individual differences in empathy would moderate the effect of embodied experiences. Participants in the IVE condition wore a HMD and saw the virtual world treated with a colorblindness filter, as seen by a colorblind individual. In other words, participants embodied the perceptual experience of being colorblind and were unable to discriminate red objects from green objects. Participants in the MS condition also wore the HMD but saw the virtual world in normal color perspective and were asked to imagine being colorblind. Participants in both conditions used a haptic device to complete a sensorimotor task relevant to the embodied experience (i.e., matching red and green screws into red and green holes). Results demonstrated that embodied experiences within IVEs have notable effects on participants measured to have predispositions of low empathy. For those participants, IVE enhanced the feeling of being ‘one’ with the colorblind person they embodied compared to the MS treatment. Furthermore, they demonstrated more favorable attitudes toward colorblind people 24 hours after the IVE experience. Considering that the duration of the embodied experience was approximately five minutes, the fact that the effect carried over to the real world 24 hours after the treatment is notable. A follow-up study examined behavioral outcomes and confirmed that participants invested twice as much time and 35 produced twice as much content to help colorblind people after embodiment in IVE compared to the participants who relied solely on imagination. Again, it is noteworthy that only a few minutes of embodying a colorblind person’s experience triggered participants to spend twice as much time helping colorblind people than participants who engaged in MS, even when this helping was completely uncompensated. The current dissertation studies aim to replicate and advance findings from these prior studies. A novel context was chosen again – pro-environmental behavior. In the first study, embodied experiences in IVE and MS were compared to determine the most effective modality to encourage pro-environmental behaviors. Participants were introduced to the environmental issue of using non-recycled toilet paper and how it leads to deforestation problems. All participants were then asked to embody a logger to experience cutting down a large tree as a result of using nonrecycled toilet paper. The study explored the degree to which actual (IVE) or imagined (MS) sensorimotor experiences can influence participants to engage in pro-environmental behaviors following their experiences. The second study gained a deeper insight of embodied experiences within IVE by manipulating the levels of immersion and interactivity separately. It should be noted that the current dissertation studies view the experience of cutting down a large tree in either IVE or through MS as cues that will make environmental issues relevant to deforestation salient, rather than an experience for participants to model. All participants were primed to think about recycling by hearing information on how using non-recycled toilet paper leads to extensive deforestation before engaging in or imagining the tree-cutting activity. This is in line with earlier research on embodied cognition that demonstrated the body-mind 36 connection by showing sensorimotor experiences (e.g., holding a hot drink and experiencing physical warmth) triggering perceptions of relevant mental schemata (e.g., perception of warmth as a personality trait). In the same way, the sensorimotor experience of cutting down a tree after being primed with environmental issues is expected to trigger pro-environmental attitude and behavior in individuals, rather than being perceived as a model intended to teach actual tree-cutting activity. Although prior literature in embodied cognition has been successful in inducing this body-mind connection based just on mental simulation (e.g., thinking about past experiences triggers individuals’ body orientation to lean backwards), the novel nature of the context of tree-cutting is expected to present challenges in initiating the body-mind link in that the mental simulation may be difficult to execute without sufficient sensorimotor cues. In comparison, the vivid sensorimotor cues provided by IVEs are anticipated to facilitate the process. Processes of Embodied Experiences Most research on embodied cognition has demonstrated the connection between the body and the mind by focusing on the outcome of embodied cognition. The current dissertation studies aim to advance these studies by looking deeper into the processes of embodied experiences. Based on earlier discussions of prior studies, the perception of presence and control are anticipated to be the underlying mechanisms driving the effects of embodied experiences. In particular, perception of personal control has been shown to lead to the belief that the self’s actions can significantly improve environmental issues and good energy behavior (Cleveland, Kalamas, & Laroche, 2005; Curtis, Simpson-Housley, & Youck, 1984; McCarty & Shrum, 2001). Because IVEs allow active interaction between the user and the mediated content through tangible sensorimotor experiences, they are likely to 37 make the sense of personal control more salient and amplify the effect of embodied experiences. Thus, the first study will compare embodied experiences in IVE and MS in terms of presence and control and explore how these variables affect proenvironmental self-efficacy and behavior. The second study will delve deeper into the process of embodied experiences by individually manipulating the level of immersion and interactivity to determine their effects on perceptions of presence and control, respectively, during embodied experiences within IVE. Furthermore, the dissertation studies will investigate the influence of embodied experiences on actual pro-environmental behavior. Many social science studies rely on self-reports of behavioral intent to assess changes in behavior, but intent to behave is not the exclusive determinant of actual behavior (Sheppard, Hartwick, & Warshaw, 1988), and inconsistencies between behavioral intention and actual behavior are repeatedly found. For example, earlier studies on recycling intentions and actual recycling behavior revealed that the relationship is spurious (Davies, Foxall, & Pallister, 2002). Self-reports of actual behavior can be inaccurate, particularly for socially desirable norms such as pro-environmental behaviors. For example, Bowman and colleagues (1998) found in a study on recycling behaviors that although 72% of respondents claimed to recycle, observation revealed that only 40% of them actually participated in recycling activity. Thus, it is important to gauge actual behavior change to supplement or compare with data from self-reports. Individual Differences in Embodied Experiences As discussed earlier, individual differences in the capacity to feel presence are anticipated to be a key moderator of the effect of presence. Several studies have found that an individual’s inherent tendency to feel empathy is positively related with the level of presence he or she feels in the virtual environment. The previously 38 conducted colorblind studies imply that individual dispositions of empathy moderate the effect of embodied experiences on helping behavior. Ramus and Killmer (2007) argued that pro-environmental behavior is a special type of prosocial behavior (i.e., behavior that is performed with the intention of promoting the welfare of an individual, group, or organization). Taken together, these results imply that there is a relationship between individual dispositions for empathy and proenvironmental behavior, and that presence may be an underlying mechanism driving the relationship. Some studies provide some empirical support for this hypothesized relationship between individual dispositions for empathy and pro-environmental attitude and behavior in that empathy levels mediate the relationship between the level of self-efficacy in terms of improving the environment and the intent for proenvironmental behaviors (Allen & Ferrand, 1999). Functional magnetic resonance imaging (fMRI) studies have also shown that individuals who self-report higher levels of empathy demonstrate different brain activity compared to those with lower empathy (Shane, Stevens, Harenski, & Kiehl, 2009). In this study, the anterior cingulate was identified as the section of the brain that is involved with feeling concern for others, and when individuals high in empathy were asked to observe another person making errors during a task, the anterior cingulate area of their brain showed significantly more activation compared to individuals low in empathy. These studies evidence the importance of considering individual differences when exploring the processes and effects of embodied experiences. Individual differences in empathy have been usually measured with Davis’ (1983) Interpersonal Reactivity Index, a 28-item scale comprised of four subscales that measure the individual’s propensity to engage in perspective taking and fantasy 39 as well as feel empathic concern and personal distress at the plight of others. Together, these subscales assess a comprehensive picture of how an individual reacts and cares about others and their needs. However, the construct most relevant to embodied experiences is likely perspective taking, which is the mental effort to step inside another person’s shoes – essentially the definition of embodied experiences. Thus, a more refined scale that measures individuals’ tendency to engage in perspective taking (Gehlbach, Brinkworth, & Wang, in press) will be used for the dissertation studies to determine how individual differences moderate the effect of embodied experiences. 40 CHAPTER SIX: DISSERTATION STUDY ONE: COMPARISION OF EMBODIED EXPERIENCES WITHIN IVE AND MENTAL SIMULATION This study directly compared embodied experiences through IVE against MS to examine the effect of different modalities of embodied experiences on proenvironmental self-efficacy and behavior. Participants were given substantive information on the use of non-recycled paper products and deforestation problems and were asked to either virtually or mentally embody the role of a person cutting down a large tree with a chain saw. In the IVE condition, participants received visual and aural sensory inputs through a HMD and input through a haptic device to experience cutting down a tree in an immersive virtual forest. In the MS condition, they received a detailed text narrative of those sensory inputs and were asked to mentally simulate the experience. Pro-environmental self-efficacy was assessed with self-report measures and pro-environmental behavior was assessed with the number of actual paper napkins used to clean a spill by participants following experimental treatment. One of the main questions of interest in Study 1 was whether the vivid experience of embodying the tree-cutter’s perspective through IVE would exert greater influence on actual pro-environmental behavior compared to mentally putting oneself in the tree-cutter’s shoes. The prior colorblind studies demonstrated that embodied experiences within IVE were able to elicit twice as much helping behavior from participants compared to those who imagined being colorblind. Based on these results IVE is anticipated to lead to greater behavioral change compared to MS: H1: Participants in the IVE condition will engage in more pro-environmental behavior than those in the MS condition. 41 IVE’s success in influencing behavior in the non-mediated real world is likely to be related to the higher levels of perceived presence felt during the embodied experience due to more explicit sensory inputs available (e.g., visual, aural, haptic) compared to MS. In addition to the self-reported measure of presence which gauges the subjective level of realism that individuals feel in a mediated context, recall on the information given (information on the environment provided from outside the mediated environment) during the experimental task will be assessed to supplement the self-reported measure. Prior studies have used memory tasks as a proxy measure of presence to complement self-reported questionnaires for improved validity (Fox, Bailenson, & Binney, 2009; Nichols, Haldane, & Wilson, 2000). The logic behind using recall as a proxy for presence is that when users are intensely engaged in an experience, they are likely to pay less attention to and remember less of the information given during the engaging experience due to limited cognitive capacity. Thus, higher recall would imply that the participant was less engaged in the world, and thus felt a lesser degree of presence. H2A: Participants in the IVE condition will report higher levels of selfreported presence than those in the MS condition. H2B: Participants in the IVE condition will demonstrate lower levels of recall than those in the MS condition. Because the tree-cutting task given as the embodied experience is novel to undergraduate participants, they will not have a previously constructed sensorimotor schema to base their mental simulation on. Based on findings from prior studies, individuals are likely to find MS difficult in these situations and thus feel less in control of their imagination. On the other hand, individuals experiencing embodiment within an IVE will receive explicit haptic input and will feel more in 42 control of their actions. H3: Participants in the IVE condition will report higher levels of control than those in the MS condition. Self-efficacy is an individual’s belief that his or her actions will have meaningful influences over events that affect their lives (Bandura, 1994). Selfefficacy is thought to determine how people feel, think, become motivated, and how they behave. Prior studies have shown that individuals who have higher levels of perceived self-efficacy have positive correlations with pro-environmental behaviors (Meinhold & Malkus, 2005; Tabernero & Hernandez, 2010). In other studies on environmental behavior, perception of control over one’s actions has been shown to lead to the belief that the self’s actions can significantly improve environmental issues and good energy behavior (Cleveland, Kalamas, & Laroche, 2005; Curtis, Simpson-Housley, & Youck, 1984; McCarty & Shrum, 2001). Because IVE is expected to elicit greater perceptions of control, it is hypothesized that: H4: Participants in the IVE condition will report higher levels of selfefficacy after the embodied experience than those in the MS condition. Based on prior findings suggesting that more realistic experiences lead to attitudinal and behavioral changes, presence is thought to be an underlying mechanism of embodied experiences. Bandura (1994) also suggests that the most effective way of creating a strong sense of self-efficacy is through actual mastery of experiences. Then, the more realistic an embodied experience is, the more it is expected to increase perception of self-efficacy. Thus, presence is also expected to be positively correlated to self-efficacy in terms of improving the environment. Because recall is an inverse measure of presence, recall is expected to be negatively correlated with self-efficacy and pro-environmental behavior. 43 H5A: Self-reported presence will be positively correlated with self-efficacy and pro-environmental behavior. H5B: Recall will be negatively correlated with self-efficacy and proenvironmental behavior. Findings from earlier studies discussed above also suggested that perception of control is positively correlated with presence, self-efficacy, and behavioral change. Thus, perception of control is expected to be another underlying mechanism of embodied experiences. H6: Control will be positively correlated with presence, self-efficacy, and pro-environmental behavior. Finally, individual differences in perspective taking propensity were explored as moderators of embodied experiences. The previously conducted colorblind studies implied that individuals with low propensities are likely to be more influenced by embodied experiences within IVE than MS. Another relevant study echoed the findings from the colorblind studies. Exposing consumers with high ability to generate mental images to imagery based appeals enhanced purchase intention, whereas the same appeal reduced purchase intention for those with lower ability to generate mental images (Petrova & Cialdini, 2005). This implies that individuals with low abilities for perspective taking may not yield favorable responses when asked to engage in MS, perhaps due to the excessive cognitive load. H7: Participants with low perspective taking propensity in the IVE condition will demonstrate higher self-efficacy and more pro-environmental behavior than those in the MS condition. Methods Sample 44 A convenience sample was obtained from the student population of a medium-sized West Coast university. The sample (N = 47) consisted of 29 women and 18 men aged 18 to 46 (M = 21.60, SD = 4.27). Participants self-reported their race/ethnicity as Caucasian/White (48.9%; n = 23); African-American/Black (14.9%; n = 7); Latino/a (10.6%; n = 5); Asian/Asian-American (17%; n = 8); and Other/mixed nationality (8.5%; n = 4)1. Apparatus The HMD used was a NVIS SX111 model which presented the virtual environment with 640 horizontal by 512 vertical pixel resolution panels for each eye with SXGA displays. Participants’ head movements were tracked by a threeaxis orientation sensing system (Intersense SDK version 4.19 with an update rate of 180 Hz) and used to continuously update the simulated viewpoint. The system latency, or delay between the participant’s movement and the resulting update in the HMD, was no greater than 80 ms. Vizard 3.0 software was used to assimilate tracking and rendering. The computer was also equipped with the Sensable Phantom Omni haptic device. For the purposes of this experiment, the device’s degrees of freedom were limited to the x-, y-, and z-axes. While most of the sawing motion occurred on the z-axes, movement in the x- and y-axes produced micro-movements that reproduced the realistic vibrations of a chain saw. The device offers up to 0.75 pounds of maximum force and allows participants to touch and feel objects in the virtual world by providing mechanical resistance based on the position of the hand as it interacts with the virtual environment. Through the tip of the haptic device, participants had one point of contact where the tip of the chain saw touched the virtual object. 45 Design All participants were subject to a pretest at least 24 hours before coming into the lab. The pretest measured individual differences in the propensity to engage in perspective taking and self-efficacy with regard to improving environmental issues. In the lab, a between-subjects design was employed and participants were randomly assigned to one of two conditions, IVE (n = 24) or MS (n = 23)2. The IVE condition presented participants with a highly immersive treecutting experience with three layers of sensory input. Figure 1 depicts the experimental setup for the IVE condition. Wearing the HMD, participants embodied an avatar standing inside a forest and saw the world from the avatar’s first person perspective in stereoscopic vision with head controlled control of point of view. Stereovision yields perception of depth within the virtual world and the head controlled point of view allows participants to look around in the virtual world as if they are in the real world. The HMD also offered spatialized sound that localized sounds in the virtual environment (i.e., chain saw, birds chirping, tree falling) according to participants’ head movements, such that if they turned their head toward an object on the left hand side, the volume would increase in relation to the angle between the ear and the virtual object. Finally, using the haptic device, participants were able to feel realistic vibrations of the chain saw they used to cut the tree with and saw the arms of the avatar move in sync with movement of their physical arms. To heighten the realism of the experience, a physical handle that resembles the handle of the chain saw used in the IVE was constructed out of cardboard and attached to the haptic device. Details such as birds flying in and out of the trees, sound of running water, and grassy terrain made the virtual forest realistic. 46 The MS condition presented participants with a narrative description of this virtual forest. To create maximum similarity between the MS condition and the rich sensory inputs offered in the IVE condition, 14 judges from a separate sample from the main study (7 males, 7 females) were asked to pretest the IVE condition to help develop the text stimulus. Two methods were combined to capture all the sensory description that the judges could come up with regarding the virtual forest. First, as the judges experienced the virtual forest and the tree-cutting procedure, they were asked to think out loud, taking care to describe every sensory detail in the virtual forest, including everything that they saw, heard, and felt. These real-time thoughts were recorded with an audio device and later transcribed. Secondly, after the judges finished cutting the tree down in the virtual forest, they were subject to a thoughtlisting procedure (Cacioppo & Petty, 1981), which asked participants to write down all of their thoughts during the augmented experience. Based on the information from transcribed audio files and the thought-listing procedures, a narrative stimulus that included all of the verbal information gathered from the 14 judges was developed for the MS condition (Appendix A). Because all of the judges experienced the same virtual forest, the sequence of events that occurred in the forest was the same for all of them (i.e., looking around the forest, sawing the tree, watching the tree fall). To develop the final MS stimulus, information that was repeated or redundant among the judges was included only once in the narrative and grammatical errors were corrected. 47 Figure 1. Experimental Setup for the IVE Condition in Study 1 (A). Participants wore the HMD (C) and were able to look around the virtual forest in stereovision and heard spatialized aural inputs wearing headphones (headphones not shown in figure). The HMD (C) was equipped with an Intersense cube that allowed head-controlled point of view in the IVE. They were then instructed to pull and push the haptic device (B) to saw the virtual tree down. Procedure Upon arrival at the lab, participants in the IVE condition first received instructions on the haptic device and were shown how to operate it. Then they were told that they would embody a “tree-cutter” in the virtual world who is about to cut down a tree. Wearing the HMD, participants entered the virtual world and saw the forest through the eyes of the tree-cutter standing in front of a tree holding onto the handle of an chain saw, poised to begin cutting the tree down in front of him or her. Figure 2 displays the series of events that the participant experiences in the IVE. 48 Before engaging in any cutting activities, participants were first asked to look around the forest, taking note of details such as birds, plants, sky, ground, and the body of the tree-cutter they were embodying. The experimenter then read out loud a short piece of information that revealed how many rolls of non-recycled toilet paper a single cord of tree is able to produce, and how many trees had been cut down to supply an average 20 year-old American with non-recycled toilet paper. Participants then heard the sound of the chain saw starting, and were instructed to begin moving the haptic device back and forth to cut the tree down. The program required all participants to engage in cutting motions for 2 minutes. After 2 minutes, participants saw and heard the tree trunk crash down to the ground and were asked to look around the forest once more. As a result of cutting the tree down, the forest was programmed to become completely quiet and all movement was removed to emphasize the damage inflicted upon the forest. Participants were then guided toward a survey computer where they filled out a series of questionnaires regarding their experience as a tree-cutter and the environmental information they recalled. For the MS condition, participants were told that they would mentally take the perspective of a “tree-cutter” who is about to cut down a tree. Instructions directed participants to try to put themselves in the shoes of the tree-cutter, imagine his or her perspective, and to think of the tree-cutter as an extension of himself or herself. They were also asked to create a vivid picture in their minds about what they see, hear, and feel in the forest while reading the narrative stimulus. Participants were then given the narrative stimulus that contains detailed descriptions of all the sensory experiences from the IVE condition. The narrative stimulus was designed to have a break in the middle where the participants in the IVE condition would receive information about using non-recycled toilet paper and 49 deforestation issues. When participants finished reading the first part of the passage, the experimenter read out the same piece of information that was given in the IVE condition, and then instructed participants to finish reading the rest of the passage. Thus, participants in both conditions received pro-environmental information at approximately the same point during the experimental treatments (i.e., after actually looking around the forest in the IVE condition; after reading the descriptions of the forest in the MS condition). When they finished reading, participants were guided toward a survey computer where they filled out a series of questionnaires regarding their experience as a tree-cutter and the environmental information they recalled. Finally, the last procedure of the experiment involved assessing participants’ pro-environmental behavior. In order to allow some time to pass after the experimental treatment so that the immediate sensitization toward environmental issues after experimental treatments would wear off, participants were asked to participate in a 30-minute long additional experiment that was completely irrelevant to the first one. Upon completion of this second experiment, participants were seated at a table that had a cup holding some water, and asked to fill out a demographic information sheet. The water was pre-measured to ensure that all participants received the same amount of water, using the same cup each time. While participants were busy filling out the form, the experimenter approached the table to gather some forms for the next participant and in the process, knocked over the cup of water. The experimenter then asked each participant for help by saying, “I’m so sorry, but I have to prepare the next participant for the experiment. Could you help me clean the water up?” and handed a pre-counted number of paper napkins to the participant. After the participant left, the number of used napkins was counted and recorded as an inverse measure of pro-environmental behavior. 50 The number of napkins that participants use would be an effective proxy for measuring pro-environmental behavior because the experimenter would be able to observe actual changes in the participant’s usage of paper products rather than relying on a self-report measure. It should also be noted that this behavior was assessed after all experimental treatment and surveys were completed and placed unsuspecting participants in a situation that required immediate response (i.e., cleaning up spilled water with napkins) without giving them time to think about socially desirable or ‘correct’ responses. This way, the experimenter was able to observe naturalistic responses outside the constraints of an experimental context. Figure 2. Screenshot of the Series of Events in the IVE Condition in Study 1. Participants saw the virtual forest in first-person perspective and were first instructed to take a good look around (A). After hearing some information on using non-recycled toilet paper and the resulting problems of deforestation, participants were instructed to begin sawing down the large tree in front of them (B). Using the haptic device, participants moved the chain saw in and out for two minutes (C) until the tree finally fell, crashing to the ground (D). 51 Measures Items for all measures included in this study can be viewed in Appendix B. Perspective Taking Propensity. This measure was administered in the pretest. Seven items from Gehlbach’s Social Perspective Taking Propensity Scale (in press) assessed each individual’s disposition to try to take the perspective of another person. Participants were asked to indicate on a 5-point scale (1 = Almost never; 5 = Almost all the time) how often they attempted to understand and try to put themselves in the shoes of another (e.g., “Overall, how often do you try to understand the point of view of other people?). Results were averaged; scores ranged from 1.86 to 5.00 (M = 3.65, SD = .70). Reliability for all seven items was Cronbach’s α = .88. As in the colorblind studies, a median split was conducted to split the participants into High Propensity (n = 25) and Low Propensity (n = 21) groups. Napkins. The number of napkins used to wipe the water off the table was counted as an inverse measure of pro-environmental behavior. The number of napkins used ranged from 0 to 12 (M = 5.11, SD = 2.39). Presence. Eleven items were used to assess participants’ experience of presence while immersed in the virtual environment or in the mentally simulated world. These items were culled from several sources (Bailenson & Yee, 2007; Nowak & Biocca, 2003; Witmer & Singer, 1998). Participants indicated on a 5point scale (1 = Not at all; 5 = Extremely) the degree to which they felt that they had embodied the tree-cutter and the extent to which they felt the forest and the tree-cutting experience were real. Responses were averaged; scores ranged from 1.17 to 4.42 (M = 2.79, SD = .84). Reliability for this measure was Cronbach’s α = .94. 52 Recall. Using the thought-listing procedure, participants were asked to remember and write down all the pieces of information on toilet paper production and its effects on the forest. Each correctly recalled information was given a point. Two raters blind to experimental conditions counted the number of correctly recalled information. Scores ranged from 0 to 3, and Cohen’s κ was .81, indicating high inter-coder reliability (Landis & Koch, 1977). Coded results from the two raters were averaged to establish a single measure of recall. Control. The Self Assessment Mannekin (SAM; Lang, 1980) assessed the level of control felt by participants during the tree-cutting process. SAM is a nonverbal, pictorial assessment technique and the semantic differential rating system is a verbal rating system to measure a person’s reaction to a stimulus. The SAM is a single pictorial item that depicts the increasing level of felt control by changes in the size of SAM (i.e., larger SAM denotes greater felt control) on a 9point scale (1 = small SAM ; 9 = large SAM). Bradley and Lang (1994) found that SAM can be easier to administer than semantic differential scales because it is a more direct measure that only requires simple judgment of explicit pictures. They also found that SAM is more accurate than semantic differential scales in terms of measuring participants’ perception of control over the stimuli. Self-Efficacy. This measure was administered once in the pretest and again after experimental treatments to capture the effect of respective treatments on selfefficacy toward environmental issues. Ten items from the Environmental Action Internal Control Index (Smith-Sebasto & Fortner, 1994) assessed participants’ perception of self-efficacy with regard to improving environmental issues. Participants answered on a 5-point scale (1 = Does not describe my point of view well; 5 = Describes my point of view very well) the extent to which they agreed to 53 statements that describe how individual actions can improve the environment (e.g., “My individual actions would improve the quality of the environment if I were to buy and use recycled paper products”). Reliability for this measure was high with Cronbach’s α = .94. Because pre-treatment self-efficacy was highly correlated with some of the dependent variables, it was entered as a covariate for subsequent analyses to control for individual differences prior to the experimental treatment. Videogame. Participants were asked to write the average time they spent playing video games each week. Familiarity with virtual environments developed by extensive exposure to video games could influence subsequent responses to the IVE condition. Earlier studies have shown that prior gaming experiences change the way that individuals respond to and navigate in virtual environments (Jelfs & Whitelock, 2001). Also, experience playing action video games has been shown to eliminate sex differences in spatial attention and decrease sex differences in mental rotation ability (Feng, Spence, & Pratt, 2007). To control for these individual differences that may lead to unwanted variance, this measure was entered as a covariate in subsequent analyses. Results Means and standard deviations for all dependent variables can be viewed in Table 1. Appendix D lists statistics for all significant and non-significant results from the analyses. 54 Table 1 Study 1 Means and Standard Deviations for Dependent Variables by Condition Napkins DV Control Presence Recall Posttreatment Self-efficacy Condition IVE M SD M SD M SD M SD M SD 4.61 2.35 5.22 1.93 2.80 .84 .75 .68 3.38 1.01 MS 5.61 2.43 3.70 2.22 2.66 .89 1.43 .83 3.70 .93 Napkins To gauge the level of actual pro-environmental behavior elicited by embodied experiences, an ANOVA was run with the number of used napkins as the dependent variable, experimental conditions and perspective taking propensity as the independent variables, and videogame hours and pre-treatment self-efficacy as covariates. The main effect of experimental condition was significant, F(1, 40) = 4.16, p < .05, partial η2 = .09, with participants in the IVE condition using significantly less napkins than those in the MS condition. H1 was supported. The main effect of perspective taking propensity was also significant, F(1, 40) = 4.73, p < .05, partial η2 = .11, with participants in the High Propensity group using significantly less napkins (M = 4.48, SD = 1.94) than those in the Low Propensity group (M = 6.75, SD = 3.41). No interaction effects were significant, and H7 was not supported. Presence and Recall An ANOVA was run with presence as the dependent variable, and the same independent variables and covariate as above. No main or interaction effects were significant, all Fs < 1. Because no significant differences in the level of presence were found between the two conditions, H2A was not supported. 55 Another ANOVA was performed with recall as the dependent variable, and the same independent variables and covariate as above. The main effect of experimental condition was significant, F(1, 40) = 6.22, p < .05, partial η2 = .14, with the IVE condition yielding significantly lower recall scores compared to the MS condition. H2B was supported. No other main or interaction effects were significant. This yields partial evidence that participants in the IVE condition felt higher levels of presence and were more engaged in the mediated environment, resulting in lower recall scores compared to those in the MS condition. Control Next, an ANOVA was performed with the single SAM item for personal control as the dependent variable, and the same independent variables and covariate as above. The main effect of experimental condition was significant, F(1, 40) = 4.44, p < .05, partial η2 = .10, with the IVE condition yielding perceptions of greater control compared to the MS condition. No other main or interaction effects were significant, all Fs < 1. H3 was supported. Self-Efficacy To compare the change in self-efficacy levels before and after the experimental treatments, a repeated-measures ANOVA was run with both selfefficacy measures as the dependent within-participants variable, and the same independent variables and covariate above as the between-participants variables. The main effect for self-efficacy was significant, F(1, 41) = 4.62, p < .05, partial η2 = .10, with significantly higher self-efficacy levels after the experimental treatments (M = 3.56, SD = .97) compared to before the treatments (M = 3.13, SD = 1.00). No other effects were significant. Because only the main effect of self-efficacy was significant, H4 was not supported and H7 were not supported. 56 Correlations among Dependent Variables Pearson correlations among all dependent variables are shown in Table 2 to take a closer look at relationships among them. Table 2 Pearson Correlations between Dependent Variables in Study 1 (N = 47) DV Napkins Presence Recall Control Pre. SE Post. SE Napkins -- .14 -.04 .11 -.16 -.10 Presence .14 -- -.17 .19 .11 .28 Recall -.04 -.17 -- -.42** .04 .05 Control .11 .19 -.42** -- -.12 -.22 -.16 .11 .04 -.12 -- .65** -.10 .28 .05 -.22 .65** -- Pre-treat SE Post-treat SE **Correlation is significant at p < .01. Contrary to expectations, self-reported presence and recall was not positively correlated with self-efficacy or pro-environmental behavior (i.e., napkins), and H5A and H5B were not supported. Control was also not positively correlated with self-efficacy or pro-environmental behavior, but was negatively correlated with recall, yielding partial support for H6. This result echoes the findings from Sas (2004) and Wallach, Safir, and Samana (2010) in which perception of control was positively correlated with the level of presence felt in the virtual environment. Finally, pre- and post-treatment self-efficacy levels demonstrated a strong 57 positive linear relationship. This implies that although there was a significant increase of self-efficacy following experimental treatment, the relative difference in self-efficacy levels between individuals were maintained over time, before and after the embodied experience. This adds support to the importance of inherent individual differences as variables in embodied experiences. Discussion This study yielded several important insights regarding embodied experiences presented through IVE and MS and how they influence self-efficacy and behavior. After experiencing rich sensory experiences of the tree-cutter in the IVE or by mentally simulating the same experience, participants in both conditions demonstrated a significant increase in self-efficacy. That is, all participants, regardless of the modality of their embodied experiences felt a higher sense that their individual actions could make significant changes to improving the environment compared to before their embodied experiences. However, differences between experimental conditions were manifested when it came to actual pro-environmental behavior. Results indicated that participants who embodied the tree-cutter in an IVE used significantly less napkins compared to participants who imagined the embodiment. Thus, it seems that increasing awareness of environmental issues through either embodied experiences within IVE or MS fosters a greater sense of self-efficacy. However, increase in selfefficacy does not always lead to actual pro-environmental behavior, as demonstrated by the napkin usage. The results of this study imply that actual sensorimotor experiences within IVEs (i.e., visual, aural, and haptic) are more powerful than mere imagination in terms of transferring over to the physical world to influence actual behavior. 58 The hypothesis that embodied experiences within IVEs would result in a higher perception of presence compared to MS was not supported by the self-report questionnaires but indirectly demonstrated with the recall measure. This partially implies that embodied experiences within IVEs seem more realistic to users compared to MS. In an effort to improve the inconsistent results between the subjective and objective measures of presence, the second dissertation study will attempt to gather richer subjective data on presence by using an enhanced presence questionnaire along with the recall measure. The inconsistency may also be explained by the fact that the presence scale used for this study was mostly intended for use after exposure to virtual environments. Using a presence scale specifically developed for narratives (e.g., Green & Brock, 2000) may have been a more sensitive measure for the MS condition. For instance, rather than asking “How much did the forest seem real?” “How much could you picture yourself in the scene of events described in the narrative?” may have been a more appropriate item to measure presence in the MS condition. The perception of control was significantly affected by the type of modality, with participants in the IVE feeling greater levels of control compared to participants in the MS condition. This result implies that individuals may not feel in control of their embodied actions when they have no previously constructed sensorimotor schema to base their mental simulation on. Contrary to expectations, presence and control were not positively correlated to self-efficacy and pro-environmental behavior. This may be due to the fact that the self-reported presence measure used in this study was not sensitive enough to pick up felt level of realism. Earlier studies have demonstrated that indirect and objective behavioral measures can better assess presence (Bailenson et 59 al., 2004). In terms of control, high interactivity may not always be the optimal solution to increase self-efficacy and favorable behavior (Sundar, 2000). Thus, Study 2 will manipulate different levels of immersion and control to obtain deeper insight into the mechanism of embodied experiences in IVEs. Finally, individual differences in perspective taking propensity did not moderate self-efficacy or pro-environmental behavior. However, participants with High Propensity did use significantly less napkins than those with Low Propensity, indicating that individual differences are involved in embodied experiences to some extent. This variable will also be further explored in the following study. 60 CHAPTER SEVEN: DISSERTATION STUDY TWO: EFFECT OF IMMERSION AND AGENCY OF CONTROL ON EMBODIED EXPERIENCES Study 2 set out to answer lingering questions on the processes of embodied experiences. Although results demonstrated that embodied experiences in IVE elicited higher recall, control, and more pro-environmental behavior than MS, it is still unclear exactly which factors of IVE led to those results. Thus, Study 2 will parse out different elements of embodied experiences in IVE, manipulating the elements of immersion and control individually to investigate its effect on selfefficacy and behavior. As previously discussed, the level of immersion is most closely related to the level of perceived presence. Although there is no standardized quantification used to divide levels of immersion, by definition, more layers of simulated sensorimotor inputs mean greater immersion. In Study 2, immersion will be varied in two levels – High Immersion (stereoscopic vision, spatialized sound, head controlled point of view, and naturalistic tactile feedback) or Low Immersion (monoscopic vision, non-spatialized sound, manually controlled point of view, and abstract tactile feedback). Control will also be varied in two levels by manipulating the agency of control – Self-Move (the participant is the entity in control of moving the saw to cut the tree down) or Other-Move (the participant follows the movement made by another participant to move the saw to cut the tree down). Presence and control failed to correlate with self-efficacy and pro-environment behavior in Study 1, but by manipulating them as independent variables, Study 2 may yield deeper insight into the processes of embodied experiences presented within IVEs. Results of Study 1 demonstrated that participants felt higher presence (as 61 measured by recall) during their embodied experience in the IVE, felt higher control in the IVE condition, and that the IVE condition ultimately yielded greater proenvironmental behavior. Other studies found that prior personal experience of recycling behavior have been found to be strong predictors of future recycling behavior (Bagozzi & Dabholkar, 1994; Boldero, 1995). Then, embodied experiences within IVEs may be sufficiently realistic and analogous to building personal experiences and the relevant sensorimotor schemata. Consequently, it is anticipated that the more immersive the embodied experience is and greater the perception of control, the greater the influence will be on pro-environmental behavior by effectively constructing a sensorimotor schema to store in the individual’s memory. H8: Participants in the High Immersion, Self-Move condition will demonstrate the greatest actual pro-environmental behavior compared to all other conditions. As discussed earlier, intent to behave does not necessarily lead to actual behavior, particularly when the behavior is considered socially desirable. Thus, selfreported intentions to engage in pro-environmental behavior will be compared to actually manifested behavior to supplement the results from Study 1. Comparing both types of measurements may yield further insight to how embodied experiences can lead to behavioral change. RQ1: How will intention to engage in pro-environmental behavior compare to actual pro-environmental behavior? Following Study 1, recall of information given during the perspective taking experience will be assessed again as a proxy measure of presence to supplement self-reported measures of presence. Based on the results from Study 1, high level of 62 immersion is hypothesized to yield high levels of recall. Also, Study 1 demonstrated that recall was negatively correlated with control. Thus, it is hypothesized that: H9A: Recall will be lower in the High Immersion condition compared to the Low Immersion condition. H9B: Recall will be lower in the Self Move condition compared to the Other Move condition. Also based on the results of Study 1, an overall increase in self-efficacy following the embodied experience, regardless of experimental condition, is expected. H10: Pre-treatment self-efficacy will significantly increase following any embodied experience. In addition to manipulating the agency of control, Study 2 will examine locus of control to assess how having self- or other-controlled haptic feedback during embodied experiences affect the degree to which participants reflect upon themselves for the environmental damage caused (i.e., cutting the tree down). Locus of control, as originally defined by Rotter (1954), refers to the extent that individuals internally attribute the cause of events that affect them. Numerous studies show that an internal locus of control is the driving factor leading to proenvironmental attitude and behavior (Balderjahn, 1988; Curtis, Simpson-Housley, & Youck, 1984; Henion & Wilson, 1976; Shrum, Lowrey, & McCarty, 1994). Using IVEs, researchers now have the freedom to manipulate the agency of control to influence the locus of control which is something that was not possible with traditional media3. Varying the level of interactivity that participants are exposed to will yield further insights on the role that control plays in embodied experiences. In the Self-Move condition, participants had active control of the haptic 63 device synced with the movement of the virtual saw cutting down the tree. In the Other-Move condition, the computer was programmed to play back movements from another participant. Thus, participants in the Other-Move condition embodied the tree-cutting avatar but passively experienced the tree-cutting by letting the haptic device guide his or her physical arms through the sawing movements. It is likely that active agents of control will place greater internal attributions about cutting the tree down (as a result of using non-recycled toilet paper) than passive agents of control. H11: Participants in the Self-Move condition will make more internal attributions for cutting the tree down compared to participants in the Other-Move condition. Finally, individual differences in perspective taking propensity were explored again to see how they moderate the effect of different levels of immersion and agency of control during embodied experiences. RQ2: How will individual differences in perspective taking propensity moderate the effect of immersion and agency of control on self-efficacy and pro-environmental behavior? Methods Sample A convenience sample was obtained from the student population of a medium-sized West Coast university. The final sample (N = 101) consisted of 60 women and 41 men aged 17 to 39 (M = 20.78, SD = 2.65)4. Participants selfreported their race/ethnicity as Caucasian/White (42.6%; n = 43); AfricanAmerican/Black (5.9%; n = 6); Latino/a (6.9%; n = 7); Asian/Asian-American (28.7%; n = 29); and Other/mixed nationality (15.8%; n = 16). 64 Apparatus The same experimental set up from Study 1 was used. The Sensable Phantom Omni haptic device was replaced with the Novint Falcon with three degrees of freedom (x, y, and z), providing up to two pounds of force feedback. By increasing the force in feedback, participants were able to receive more realistic tactile input of the chain saw. Design All participants were subject to the pretest used in Study 1 at least 24 hours before the experimental treatment, assessing their level of perspective taking propensity and pre-treatment self-efficacy. In the lab, participants were randomly assigned to a condition following a 2x2 between-participants design. One independent variable was Agency of Control, separated into Self-Move and Other-Move, which manipulated the person in control of the saw movements. The second independent variable was Immersion, separated into High and Low Immersion, which manipulated the number and range of sensory inputs that the participant received while exposed to the virtual environment. Table 3 describes the operationalization of each cell in greater detail. 65 Table 3. 2x2 Between-Participants Design for Study 2 Other-Move Self-Move Low Immersion (Desktop) Participant views the virtual world using a desktop monoscopic monitor without spatialized sound. Participant enters the virtual world in first person perspective. Participant manually controls the point of view using a mouse. Participant has no control of the saw. High Immersion (HMD) Participant wears a HMD with stereoscopic display and spatialized sound. Participant enters the virtual world in first person perspective. Participant has head controlled point of view. Participant has no control of the saw, but is guided by the movement made by another participant through holding the haptic device. Participant views the virtual Participant wears a HMD with stereoscopic screens and world using a desktop spatialized sound. Participant monoscopic monitor without enters the virtual world in first spatialized sound. Participant person perspective. Participant enters the virtual world in first has head controlled point of view. person perspective. Participant manually controls the point of Participant controls the saw, view using a mouse. making physical sawing Participant controls the saw with movements with the haptic device to cut the tree down. a button. Each button press moves the saw once. To control for variance in the tree-cutting movement that participants experience in the Other-Move condition, tracked information from the participant in the Self-Move condition directly preceding the Other-Move condition was used as the stimulus presented in the Other-Move condition. That is, the saw movement made by participants in the Low Immersion/Self-Move condition and High Immersion/Self-Move condition was recorded and played back for participants watching the tree being cut down in the succeeding Low Immersion/Other-Move condition and High Immersion/Other-Move conditions, respectively. Yoking participants between these conditions was planned in advance in the experimental design to ensure that the tracked information for each participant in 66 the Self-Move condition was used once for each participant in the Other-Move condition. Consequently, across the two conditions the movements experienced as a whole were quite similar. Procedures Low Immersion/Self-Move condition. Upon arrival at the lab, participants received instructions on the haptic device and were shown how to operate it. Then they were told that they would gain personal experience of cutting a tree down by embodying the body of a tree-cutter who is about to cut down a tree. At a desktop computer station, participants saw the virtual forest used in Study 1 (monoscopic vision). Participants were able to move their point of view manually using a mouse and were given headphones to wear to receive aural inputs. Figure 3 depicts the experimental setting for the Low Immersive/Self-Move condition. Figure 3. Experimental Setup for Low Immersion, Self-Move Condition in Study 2. Participants wore headphones for non-spatialized aural input, and pressed the spacebar to control the chain saw. 67 Before engaging in any cutting activities, participants were first asked to look around the forest using the mouse, taking note of details such as birds, plants, sky, ground, and the body of the tree-cutter they were embodying. While looking around in the world, participants heard a pre-recorded audio file narrating the information on toilet paper usage and deforestation used in Study 1. Afterwards, participants heard the sound of the chain saw starting and were instructed to hit the spacebar to move the saw to cut the tree down. Each spacebar press moved the saw in and out once. All other procedures were same as Study 1. After spending 2 minutes cutting down the tree, participants were guided toward a survey computer where they filled out a series of questionnaires regarding their experience as a treecutter. Low Immersion/Other-Move condition. Participants experienced the same virtual forest under the same experimental setup as the Low Immersion/Self-Move condition. However, these participants had no control of the saw. Rather, the movements of the saw made by the participant in the preceding Low Immersion/Self-Move condition were tracked and played back such that the haptic device pulled and pushed the participants’ physical arms. In essence, participants in the Low Immersion/Other-Move condition did not actively cut the tree down but watched the recorded movie of another participant cutting the tree down for 2 minutes. High Immersion/ Self-Move condition. Participants experienced the virtual forest with a rich array of sensory information. Participants wore the HMD and saw the forest in stereoscopic vision with spatialized audio and had head-controlled point of view. They were also given full control of the haptic device to cut the tree down. As in Study 1, the physical movement of the haptic device made by the 68 participant was synchronized to the movement of the virtual arms of the tree-cutter. Participants engaged in active tree-cutting movements for 2 minutes. High Immersion/Other-Move condition. Participants experienced the virtual forest in stereoscopic vision and spatialized sound and were given head-controlled point of view, but had no control of the saw. In this condition, participants held on to the handles on the device while the computer guided the movement of their hands. Similar to the Low Immersion conditions, the haptic device’s movement was a playback of the movements the participant in the preceding High Immersion/SelfMove condition made. Measures All specific survey items can be found in Appendix C. Perspective Taking Propensity. The same measure from Study 1 was used. Reliability for all seven items was Cronbach’s α = .81. Scores ranged from 2.29 to 5.00. A median split was conducted to split the participants into High Propensity (n = 49) and Low Propensity (n = 52) groups. Manipulation Check for Agency of Control (SAM). The SAM used in Study 1 assessed the successful manipulation of Self-Move and Other-Move conditions. Scores ranged from 1 to 9 (M = 4.83, SD = 2.15). Manipulation Check for Immersion (Presence). A refined measure of presence was administered to check the successful manipulation of High and Low Immersion conditions. Six items from Ratan’s (2010) Self Presence Questionnaire and 11 items from the ITC-Sense of Presence Inventory (Lessiter, Freeman, Keogh, & Davidoff, 2001) were adapted to fit the current study. Reliability for this measure was Cronbach’s α = .93. Responses were averaged; scores ranged from 1.00 to 4.06 (M = 2.78, SD = .75). 69 Napkins. The same behavioral measure from Study 1 was used. The number of napkins used ranged from 0 to 14 (M = 8.01, SD = 3.33). Behavioral Intention. Five items were created to assess participants’ intentions to engage in recycling behavior. Five-point, fully labeled Likert scales measured the extent to which they planned to engage in recycling. Reliability for this measure was Cronbach’s α = .80. Responses were averaged; scores ranged from 1.00 to 4.20 (M = 2.70, SD = .73). Recall. The recall measure from Study 1 was used. Scores ranged from 0 to 8 (M = 3.47, SD = 1.53), and Cohen’s κ was .70, indicating good inter-coder reliability (Landis & Koch, 1977). Coded results from the two raters were averaged to establish a single measure of recall. Self-Efficacy. The measure from Study 1 was used again for pre- and posttreatment assessments. Reliability for this measure was high with Cronbach’s α = .93 for both the pre- and the post-treatment self efficacy items. As in Study 1, this measure was entered as a covariate in subsequent analyses to control for individual and sex differences. Locus of Control. Three items from the Revised Casual Dimension Scale (CDSII; McAuley, Duncan, & Russell, 1992) were used. Participants were first asked to respond an open-ended question about the reason they (i.e., through the tree-cutter) cut the tree down in the virtual forest. The scale items then asked them to think about those reasons and to indicate the extent to which they agreed to 9point semantic differential scales that measure the locus of control (1 = Internal locus of control; 9 = External locus of control). Specific items can be found in Appendix C. Reliability for this measure was Cronbach’s α = .76. Responses were averaged; scores ranged from 1.00 to 6.33 (M = 2.98, SD = 1.30). 70 Videogame. As in Study 1, average weekly hours of videogame play was entered as a covariate to control for individual variances. Results Means and standard deviations for all dependent variables can be viewed in Appendix E. Manipulation Checks An ANOVA was run with SAM as the dependent variable, agency of control, immersion, and perspective taking propensity as the independent variables, and videogame hours and pre-treatment self-efficacy as covariates. The main effect of agency of control was significant, F(1, 91) = 6.30, p < .05, partial η2 = .07, confirming the success of manipulation between the Self-Move and Other-Move conditions. All other effects were non-significant. Another ANOVA was run with presence scores as the dependent variable and the same independent variables and covariates. The main effect of immersion was significant, F(1, 91) = 9.59, p < .01, partial η2 = .10, confirming the success of manipulation between the High and Low Immersion conditions. All other effects were non-significant. Behavioral Intention and Napkin Use An ANOVA was run with behavioral intention as the dependent variable and the same independent variables and covariates as above. The main effect of perspective taking propensity was significant, F(1, 91) = 4.52, p < .05, partial η2 = .05, with participants with High Propensity reporting significantly higher intentions to recycle (M = 2.74, SD = .66) than participants with Low Propensity (M = 2.67, SD = .79). No other effects were significant. Next, the same ANOVA was run with actual behavior (i.e., napkins) as the 71 dependent variable. As shown in Figure 4, the interaction between agency of control and perspective taking propensity was significant, F(1, 91) = 4.86, p < .05, partial η2 = .05. Posthoc analyses with Tukey’s HSD revealed that participants with Low Propensity used significantly less napkins when they experienced the Other-Move condition (M = 7.30, SD = 3.29) than the Self-Move condition (M = 8.60, SD = 3.54), whereas participants with High Propensity used significantly less napkins when they experienced the Self-Move condition (M = 7.35, SD = 3.64) than the Other-Move condition (M = 8.96, SD = 2.55). All other main and interaction effects were non-significant, and H8 was not supported. Figure 4. Interaction between Agency of Control and Perspective Taking Propensity on Napkin Use in Study 2 Recall An ANOVA was run with recall as the dependent variable and the same independent variables and covariates. The main effect of immersion was significant, F(1, 91) = 6.24, p < .05, partial η2 = .06, with participants in the High Immersion 72 condition recalling significantly less information (M = 3.13, SD = 1.42) compared to participants in the Low Immersion condition (M = 3.81, SD = 1.58). Also, selfreported presence measures from the manipulation check above confirmed that High Immersion conditions are higher in presence than Low Immersion conditions and this result further confirms that recall is an effective proxy measure of selfreported presence. H9A was supported. However, the main effect of agency of control was not significant, and H9B was not supported. Self-Efficacy To compare the change in self-efficacy levels before and after experimental treatments, a repeated-measures ANOVA was run with both self-efficacy measures as the dependent within-participants variable, and the same independent variables and videogame hours as the covariate. The main effect for self-efficacy was significant, F(1, 92) = 41.93, p < .01, partial η2 = .31, with significantly higher selfefficacy levels after the experimental treatments (M = 3.65, SD = .79) compared to before the treatments (M = 3.22, SD = .75), regardless of experimental condition. H10 was supported. In addition, the interaction between self-efficacy and perspective taking propensity was also significant as shown in Figure 5, F(1, 92) = 8.91, p < .01, partial η2 = .09. 73 Figure 5. Interaction between Self-Efficacy and Perspective Taking Propensity Over Time in Study 2 Posthoc analyses with Tukey’s HSD revealed that for participants with High Propensity for perspective taking, self-efficacy became significantly higher post-treatment (M = 3.78, SD = .68) than pre-treatment (M = 3.52, SD = .54). Also for participants with Low Propensity for perspective taking, self-efficacy became significant higher post-treatment (M = 3.53, SD = .87) than pre-treatment (M = 2.95, SD = .82). The post-treatment self-efficacy score for the High Propensity group was significantly higher than all other conditions. Posthoc tests also revealed that embodied experiences were more effective for participants with Low Propensity than those with High Propensity in that individuals with Low Propensity experienced twice as much increase in self-efficacy (.26 mean score difference) following the embodied experience compared to those with High Propensity (.58 mean score difference). 74 Locus of Control An ANOVA was run with locus of control as the dependent variable and the same independent variables and covariates. The main effect of agency of control was significant, F(1, 91) = 4.73, p < .05, partial η2 = .05, with participants in the Self-Move condition making more internal attributions for the environmental damage (i.e., cutting the tree down) (M = 2.70, SD = 1.22) compared to participants in the Other-Move condition (M = 3.26, SD = 1.32). H11 was supported. Correlations Among Dependent Variables Once again, Pearson correlations among all dependent variables are shown in Table 4 to take a closer look at relationships among them. Table 4 Pearson Correlations between Dependent Variables in Study 2 (N = 101) L. DV Napkins Intention Recall Pre. SE Post. SE Control Napkins -- -.01 -.04 -.10 -.09 -.07 Intention -.01 -- .24** -.02 .56** .64** Recall -.04 .24** -- -.00 .26** .16 L. Control -.10 -.02 -.00 -- .16 .07 -.09 .56** .26** .19 -- .75** -.07 .64** .16 .07 .75** -- Pre-treat SE Post-treat SE **Correlation is significant at p < .01. 75 Aside from pre-treatment self-efficacy, which was considered to be an inherent individual difference in Studies 1 and 2, there were some additional correlations among the dependent variables to note. Behavioral intention was positively correlated with pre- and post-treatment self-efficacy. Earlier studies have demonstrated that self-efficacy is a good predictor of pro-environmental intentions (DeYoung, 1986) which explains the positive correlation between intention and self-efficacy. The correlation for post-treatment self-efficacy is higher than pre-treatment self-efficacy, suggesting that self-efficacy becomes a better predictor of recycling intentions following the embodied experience of cutting a tree down. Recall is also positively correlated with behavioral intention, implying that participants develop greater intention to recycle when they perceive less presence during the embodied experience. This is an inconsistency that cannot be explained with current data and should be explored further in future studies. However, it should be noted that the correlation between recall and behavioral intention was relatively low (r = .24) and may be a spurious finding. Finally, pre- and post-treatment self-efficacy levels demonstrated a strong positive relationship, replicating correlations from Study 1. Discussion These results yield important insights into the role of immersion and agency of control in the process of embodied experiences. Level of immersion directly influenced the realism that participants felt during the embodied experience (i.e., presence, recall). Participants in the High Immersion condition felt significantly higher levels of presence compared to those in the Low Immersion condition and thus self reported more presence and also recalled less information 76 presented while they were engaged in the embodied experience. Agency of control directly influenced the level of internal attributions (i.e., locus of control) participants made for the vicarious experience of tree-cutting. Participants who had active control of their actions in the Self-Move condition perceived greater control and made greater internal attributions for their actions compared to those who embodied the tree-cutter and had passive control in the Other-Move condition. This implies that having active haptic control in IVEs induces greater sense of personal responsibility for that action. Presence and recall differed significantly only when levels of immersion were varied, and not by agency of control. This implies that increasing the overall level of immersion through layers of sensorimotor stimuli is more effective in creating a realistic embodied experience compared to providing layers of just motor stimuli (i.e., haptic control). Individual differences in perspective taking propensity directly influenced recycling intentions and moderated the level of increase in actual behavior and selfefficacy. Participants with High Propensity self reported significantly higher intentions to engage in pro-environmental behavior compared to Low Propensity individuals, which replicates the result of actual napkin use in Study 1. But in Study 2, actual usage of napkins was influenced by agency of control. Low Propensity participants used significantly less napkins when they experienced the Other-Move condition, and High Propensity participants used significantly less napkins when they experienced the Self-Move condition. It seems that when it comes to actual pro-environmental behavior, Low Propensity individuals perform significantly better when they are given guided movements. These results replicate the previously discussed colorblind studies in that participants with low ability to 77 understand other minds or others’ experiences seem to be helped more significantly by embodied experiences presented in IVEs compared to those with high abilities. A possible explanation may be that without previously constructed sensorimotor schema, Low Propensity individuals may find it more difficult than High Propensity individuals to immediately construct a new schema on their own. Consequently, they seem to benefit more from the guided movements in the OtherMove condition than High Propensity individuals. On the other hand, individuals with High Propensity for perspective taking demonstrated greater proenvironmental behavior when they were given active haptic control. Results imply that these individuals have higher intention to engage in pro-environmental behavior compared to participants with Low Propensity, but they seem to require embodied experiences with active haptic control in order for their intentions to connect to actual pro-environmental behavior. It may be that having active haptic control and actually making the motor movements on their own during the embodied experience aids High Propensity individuals in constructing novel sensorimotor schemata during the embodied experience. Finally, all participants felt a significant increase in their self-efficacy in terms of improving the quality of the environment following any embodied experience, replicating findings from Study 1. But more specifically, participants with Low Propensity for perspective taking demonstrated greater increases in selfefficacy after the embodied experience compared to participants with High Propensities. This replicates findings from the previous colorblind studies in which Low Propensity individuals demonstrated more favorable attitudinal changes than those High Propensity individuals after embodied experiences in an IVE as a colorblind person. 78 CHAPTER EIGHT: CONCLUSION Summary of Findings Study 1 revealed that embodied experiences in IVE and MS can both significantly increase the belief that the self’s actions could improve the quality of the environment. But this increase in self-efficacy was only connected to actual proenvironmental behavior when participants experienced the tree-cutting experience through IVE. IVE elicited significantly higher perceptions of presence and control compared to MS. Thus, the results of Study 1 suggested that presence and personal control may be the processes through which embodied experiences influence selfefficacy and pro-environmental behavior. Study 2 delved deeper into these underlying mechanisms by manipulating the level of immersion and agency of control of the embodied experience. Levels of immersion were manipulated by increasing the layers and the degree of vividness of visual, aural, and haptic sensorimotor inputs provided to the participant. Higher level of immersion resulted in higher self-reported presence and lower recall compared to Lower level of immersion. Agency of control was manipulated by allowing participants to either actively control the haptic device on their own or to passively follow the movements made by another participant. Participants who had active control in the Self-Move condition made greater internal attributions for the damage they caused to the environment (i.e., tree-cutting activity) compared to those who merely followed guided movements recorded by another participant. In both studies, any form of embodied experience, regardless of the level of immersion or the agency of control, increased self-efficacy. But Study 2 revealed that individual differences moderated the increase of self-efficacy with participants 79 with Low Propensity for perspective taking felt greater increases in self-efficacy after the embodied experience than those with High Propensity. These results imply that embodied experiences had a greater influence on Low Propensity individuals. Individual differences also moderated recycling intentions and actual proenvironmental behavior. High Propensity individuals demonstrated higher intentions to engage in pro-environmental behavior (Study 2) and actually engaged in greater pro-environmental behavior (Study 1) compared to Low Propensity individuals. However, High Propensity individuals engaged in significantly more pro-environmental behavior when they had active haptic control of the motor movements during the embodied experience. Conversely, Low Propensity individuals needed guided haptic movement during the embodied experience to actually engage in pro-environmental behavior. Theoretical Implications – Embodied Cognition Theorists have posited that virtual environments may be effective tools to study the relationship between the body and the mind (Velmans, 1998), but few, if any, studies have presented empirical support. The current dissertation studies are, to the best of my knowledge, the first to demonstrate IVEs’ capacity to offer embodied experiences that are sufficiently real to influence attitude and, more importantly, actual behavior based on their virtual experience. My results confirmed that embodiment through IVEs are more influential than MS (Study 1). Despite the vivid descriptions of the tree-cutting process provided in the MS condition, actual sensorimotor experiences during embodiment in IVE were more influential in encouraging behavioral changes in the physical world. Results also confirmed that the behavioral change may be moderated by individual differences in the propensity for perspective taking and the agency of control (Study 2). 80 These results demonstrated that the effect of feeling vivid sensory cues and making actual motor movements in IVEs are able to transfer into the physical world to change actual behavior. Considering that participants were exposed to the embodied experience within IVEs for about three minutes, the fact that this limited exposure was able to decrease napkin usage by approximately 20 percent in both studies is striking. Open-ended responses asking participants to guess the purpose of the experiment ensured that none of the participants included in the final dataset were consciously aware of using less napkins. This is certainly not a result of modeled behavior as participants were not learning how to cut down a tree through the embodied experience. Embodying the novel experience of tree-cutting in the IVE after being primed with environmental issues seems to have triggered or constructed relevant pro-environmental mental schemata to later influence attitude and behavior in the physical world. The theory of embodied cognition stipulates that the experience, perception, and retrieval of embodied stimuli are closely linked and highly overlapping. Niedenthal (2007) notes that through the interconnection of neurons that were active during the original experience (e.g., seeing and hearing walnuts being cracked), only partial activation of relevant neurons (e.g., only hearing walnuts being cracked) can begin a cascade to trigger the activation of the complete set of neurons (e.g., as if one has both seen and heard walnuts being cracked). Following this logic, it is possible that the vivid experience of tree-cutting in the IVE may have been interconnected with the information on non-recycled paper products and deforestation given to participants during construction of mental schemata. Being faced with a situation where they had to use paper napkins (to clean up the water) may have activated schemata constructed during the 81 experimental treatment on using paper products and deforestation as well as the vivid experience of cutting down a tree, ultimately eliciting participants to unconsciously use less napkins. Similarly, it is likely that the partial activation of relevant neurons, such as hearing the chain saw or watching a tree fall, may have elicited pro-environmental behavior. IVEs will be able to significantly expand the research on embodied cognition by liberating users from the physical constraints of the body in the virtual world (e.g., homuncular lobster). One of the main claims of embodied cognition scholars are that cognition is “situated” (Wilson, 2002). In other words, cognition is not an abstract and hard-wired entity that stands exclusively on its own, but rather occurs in dynamic interactions with the body and the surrounding environment. Another claim is that our thoughts and feelings are bound by our body. For example, humans think and feel differently from a puppy because of the biological frame that encases our mind – using fingers to grip, walking on two feet, and using our tongue to speak languages. The current dissertation demonstrated that these boundaries can be infinitely expanded with embodied experiences in IVE where users can construct sensorimotor schemata embodying any self-representation in any situational context. For instance, virtual environments allow individual to embody virtual representations of different physical stature (Yee & Bailenson, 2007), sex/gender (Yee, Ducheneaut, Yao, & Nelson, 2011), nationality (Groom, Bailenson, & Nass, 2009), and those with physical disabilities (Ahn & Bailenson, 2010; Kalyanaraman, Penn, Ivory, & Judge, 2010). Taking advantage of the flexibility that virtual environments provide in terms of self representation and environment, users are able to build sensorimotor schemata that will later influence perception and behaviors without having to experience the situation in the real world. 82 At the same time, IVEs can provide realistically vivid sensorimotor cues that make the embodied experience more tangible than mere imagination. This is a crucial advantage of IVEs because the importance of actual experiences in forming sensorimotor schemata has been demonstrated in a recent study by Flusberg and Boroditsky (2011). By having participants physically experience rotating the wooden block figures presented in Shepard and Metzler’s (1971) mental rotation task, results revealed that if participants find the physical rotation task to be difficult, they will take longer to mentally simulate themselves physically rotating the same object. Conversely, when participants were asked to mentally simulate the objects rotating on their own (rather than the participants moving the object), the difficulty of the physical task had no influence on how long they took to complete the mental simulation. Thus, it seems that sensorimotor experiences that involve the self are encoded separately from imagining the same situation without the self as the actor. This is similar to the activation of canonical neurons discussed earlier (Di Pellegrino, Fadiga, Fogassi, Gallese, & Rizzolatti, 1992), that respond selectively to three-dimensional objects based on their shape, size, and spatial orientation. Using IVEs, participants have the flexibility of the situated context, but are actively able to experience the tangible sensorimotor stimuli of seeing, hearing, and feeling. MS is also able to yield extensive freedom in terms of flexibility of situated context (i.e., imagination is also free from many restraints of the physical world). However, results of the current dissertation studies indicate that IVEs’ capacity for vivid sensorimotor experiences may be a critical difference between embodied experiences in IVE and MS, leading to changes in pro-environmental self-efficacy and actual behavior. Because the vivid sensorimotor experience in the IVE led participants to feel as if they were actively playing a part in causing deforestation by 83 cutting a tree down in the IVE forest, they may have felt greater personal responsibility for the damage they incurred to the forest compared to participants who merely imagined cutting down a tree. Another important theoretical implication from the results of the current dissertation is that individual differences in the capacity to feel presence and respond to embodied experiences may be overcome with IVE. The encoding and retrieval of embodied experiences is moderated by individual differences in the sense that aspects of the experience most salient and important for the individual are selectively preserved for future retrieval (Barsalou, 2003). In the colorblind studies that I conducted previously, individuals with low propensity for empathy felt greater similarity and developed more favorable attitudes toward colorblind people compared to those with high propensities when they were provided with visual aids from embodied experiences within IVEs. Study 2 of the current dissertation replicated this effect. When Low Propensity individuals received guided motor movements from another participant, the embodied experience successfully translated into pro-environmental behavior in the physical world. Although further investigations are needed to determine the exact underlying process, these results imply that if Low Propensity individuals have difficulty in forming a novel sensorimotor schema on the spot during the embodied experience, providing them with guided sensorimotor cues may help. In Study 2, the individual difference in capacity between Low and High Propensity groups was virtually eliminated with guidance, and Low Propensity individuals engaged in just as much proenvironmental behavior as High Propensity individuals. Theoretical Implications – Immersion and Presence in Virtual Environments The results also contribute to the body of research on virtual environments 84 by individual manipulating and analyzing the relationships between the functional features of virtual environments (i.e., immersion, agency of control) and the subjective responses to these functional features (i.e., presence, perception of control). In addition, my findings on how individual differences moderate these processes will provide much needed empirical evidence in this field. Not many studies to date have compared IVEs to MS in terms of how individuals perceive presence. This may be because scholars generally assume that the rich sensorimotor inputs provided within IVEs would naturally be more realistic compared to imagination. However, there is empirical evidence to the contrary which confirms that imagination may be more effective in producing vivid sensorimotor cues. For instance, a narrative description of less than 45 words has been shown to be more influential in forming false memories compared to digitally manipulated photos (Garry & Wade, 2005). Also, imagery based advertisements actually lowered purchase intentions for individuals with low ability to generate mental imageries (Petrova & Cialdini, 2005). Results from the current dissertation confirmed that IVE elicits higher perception of presence (Study 1), but that only certain elements of the virtual environment influence presence perception (Study 2). Contrary to my hypothesis, Study 2 revealed that adding layers of sensory input (i.e., immersion) significantly increased presence, but not adding layers of motor input (i.e., agency of control). It seems that increasing the sense of presence through vivid sensory inputs should precede adding interactivity or motor inputs when constructing embodied experiences within virtual environments. In fact, Study 2 results imply that having active motor control during an embodied experience may not be beneficial for everyone – only individuals with High Propensity for perspective taking benefited 85 from active motor control. These results replicate those of Slater and colleagues (2010). They placed participants in a similar IVE setup as the current dissertation study using a HMD and participants received three layers of sensorimotor inputs – visual, behavioral mimicry, and touch. Of the three, they discovered that visual immersion by way of stereoscopic vision and first-person perspective clearly dominated as an explanatory factor for the perception of presence. Taken together with the results of the current dissertation, it seems that the perception of presence is elicited mainly by sensory cues rather than motor cues, and that presence does not necessarily increase unconditionally with more layers of sensorimotor input. Theoretical Implications – Environmental Studies Most empirical studies in the realm of environment research have resorted to self-report measures of behavioral intentions rather than observe actual behavioral change as a result of experimental treatment, following the tradition of theory of reasoned action (Fishbein & Ajzen, 1975) which predicts a positive correlation between behavioral intention and actual behavior. However, as earlier studies and the current dissertation studies demonstrate, self-efficacy and intention may not be effective predictors of actual pro-environmental behavior. This gap may be from social desirability bias (Fisher, 1993) in which respondents choose to report “desirable” or socially accepted behaviors in surveys even if they do not reflect accurate intentions (Sherman, 1980; Malhotra, 1993). Perception of control may also play a role in creating a gap between intention and behavior in that the behavior must be under complete volitional control (Ajzen & Fishbein, 1980). That is, the individual must be free to decide at will to perform or not perform the behavior without external barriers. 86 In the current dissertation studies, participants were asked to voluntarily help clean up spilled water using however many napkins they wished to use. By choosing an unobtrusive method of measuring behavior, I was able to obtain naturalistic responses outside of the experimental context. Also, because the water was spilled without notice, participants did not have time to worry about the socially desirable or correct answer, decreasing possible confounds of social desirability or demand characteristics5. Open-ended responses which asked participants to guess the purpose of the experiment confirmed that none of the participants included in the final datasets for both studies in the current dissertation were aware of the purpose of the behavioral measure. That is, none of the participants were able to consciously connect the napkin usage to their embodied experience in the IVE or the MS treatment. Thus, a strong theoretical contribution that these studies make is that self-reported measures of self-efficacy and behavioral intention are assessed and compared against actual observation of paper conservation. Alternative Theoretical Explanations Despite increasing interest and expanding empirical evidence on embodied cognition, scholars are still unsure of the underlying mechanisms of how exactly the experience, perception, and retrieval of embodied experiences work (Pezzulo et al., 2011). The current dissertation demonstrated that embodied experiences in IVEs may be influenced by different levels of immersion and agency of control and moderated by individual differences in the propensity to engage in perspective taking. However, there is still much to be learned about the exact processes of embodied experiences. Although the framework of embodied cognition provides partial explanation for the connection between embodied experiences in IVEs and 87 the resultant changes in attitude and behavior in the physical world, it may be worthwhile to consider other theories that may supplement the theory of embodied cognition in terms of understanding processes and underlying mechanisms. One such theory is Zillman’s theory of excitation-transfer (1983), which purports that the excitation or arousal from one stimulus can amplify the response to another stimulus. For instance, if an individual is aroused by watching a violent film, the residual excitement from this experience would amplify aggressive behavior in an event that immediately follows the originally arousing experience, compared to an individual facing the same event who did not experience the arousing experience. This theory may provide further insight as to why IVE was more effective than MS in eliciting greater pro-environmental behavior. Based on this theory, vivid sensorimotor cues provided during the tree-cutting experience in the IVE were likely to have led to greater arousal compared to mere imagination. This excitation may have transferred into the physical world, triggering participants in the IVE condition to engage in greater pro-environmental behavior compared to those in the MS condition (Study 1). However, it should be noted that the pro-environmental behavioral measure in the current studies was gauged by observing the inhibition of behavior – using less paper napkins. In this sense, the observed behavior in the current dissertation studies yielded results that are the complete opposite of what would be expected based on the excitation-transfer theory. That is, the theory would anticipate that the IVE condition would yield greater arousal due to vivid sensorimotor cues provided during the embodied experience compared to the MS condition. Heightened arousal, in turn, would lead to greater manifestation of behavior – more napkin usage. However, the results from Study 1 demonstrated that embodied experiences in IVE 88 actually led to less napkin use compared to the MS condition. This result discounts the possibility of excitation and arousal driving the observed pro-environmental behavior. Another alternative explanation for the behavioral differences between the two conditions may be that embodied experiences within IVEs trigger different cognitive responses compared to MS. According to Schachter and Singer’s two factor theory of emotion (1962), individuals experience emotional states based on how their minds label the physiological excitation. For instance, when participants interacted with a person of the opposite-sex in a highly arousing situation (i.e., on a suspension bridge), they were likely to label the physiological excitation of standing on a bridge as sexual attraction to the opposite-sex individual and later perceived that individual as more attractive compared to participants who were in less precarious locations (i.e., on a low, sturdy bridge) (Dutton & Aron, 1974). The Schachter-Singer theory proposes that when individuals have no clear causal explanation about their state of arousal, they will label arousal in terms of available cognitions. Following this logic, it is possible that participants who experienced the IVE condition in the current dissertation felt higher arousal compared to those in the MS condition, and attributed the arousal to the information on using non-recycled paper products and deforestation that they were primed with at the beginning of the experiment. Consequently, it is likely that these participants labeled their arousal as guilt or personal responsibility as a result of contributing to the deforestation problem. Lang’s limited capacity model of mediated message processing (2000) also makes predictions relevant to arousing content of mediated experiences. According to this model, arousing mediated content would allot greater cognitive resources for 89 the storage of the given information, which means less resource would be available for encoding. This means that the overall amount of information encoded may be reduced, but that the information that is encoded will be well stored. Relevant studies show that emotionally arousing topics or the occurrence of such arousing events are recalled well, but the specific information contained in the message is remembered less well (Christianson, Goodman, & Loftus, 1992; Heuer & Reisberg, 1992). Applied to the results of the current studies, Lang’s model may explain why significant changes to actual behavior could be observed in participants who were in the IVE condition with arousing stimuli, when their recall scores were actually lower than participants in the MS condition. That is, because the MS condition was less arousing, participants may have had greater cognitive resources for encoding specific information but less for storage. On the other hand, participants in the IVE condition may have encoded less specific information but had more cognitive resources for storage, implying that the information that was encoded was stored well enough to influence their sensorimotor schemas and future behaviors. Future research exploring embodied experiences in IVEs should take these alternative explanations into consideration as possible underlying mechanisms that drive attitudinal and behavioral changes as a result of embodied experiences. In depth investigation of affect, arousal, and cognitive activities in response to embodied experiences will yield greater insight into how embodiment is processed by individuals and why they are motivated to change the way that they think and behave in the physical world as a result of their virtual experience. Applied Implications The finding that vivid sensorimotor inputs presented through IVEs are able to aid in the embodiment of completely novel experiences opens up great potential 90 for applications. For instance, public service announcements promoting proenvironmental behavior could become significantly more persuasive when presented as an embodied experience in virtual environments rather than relying on traditional media. Considering that a child between the ages of 8 and 18 spends an average of nearly 1.5 hours at a computer and 1.25 hours playing video games every day (Kaiser Family Foundation, 2010), the content of the public service announcement could easily be designed into a video game. With the advent of games with higher immersive features such as the Nintendo Wii or the Microsoft Kinect, IVEs are becoming increasingly ubiquitous (Ahn, Fox, & Bailenson, in press). Because video games played in IVEs have been found to be more influential in terms of perception of presence and influencing behavior (Perksy & Blascovich, 2007; 2008) pro-environmental messages relayed through IVEs are likely to be more persuasive than using traditional media. Furthermore, based on the results from the previously conducted colorblind studies and the current dissertation studies, IVEs seem to be powerful enough to influence attitude and behavior in any other novel context of embodiment. Thus, public service announcements may be designed for highly immersive video game platforms to relay messages on a wide range of themes such as health behavior or safety. In addition, the results also imply that individual differences in the capacity to feel presence can be important factors that moderate the effect of embodied experiences. This implies that content developers can tailor the message to meet the needs of their target audience. By collecting data on individual differences such as perspective taking propensity, more effective content of embodiment may be developed to subject the individual to maximal influence from the experience. For 91 instance, for people with low propensity for perspective taking, the embodied experience would provide sensorimotor aids that guide individuals to desirable behavior. On the other hand, people with high propensities would be given full control of the sensorimotor experience to learn through the embodiment. In the same way, embodied experiences in IVE could significantly help those involved in training and education. Lindgren (2009) found that embodying an expert’s visual point of view in a navigating and search task significantly improved task performance. In the same way, individuals could train and learn either through active or guided sensorimotor experiences presented within IVEs. More importantly, the training session can be tailored to meet each student’s needs. For instance, if a student needs guided rather than active experiences, the student can practice the guided movements for as long as he or she feels comfortable and then move on to active experiences. Also, as demonstrated in Study 2, the sensorimotor movements of a particular individual can be accurately tracked in the virtual environment and played back to other users. This implies that experts’ sensory perceptions and motor movements may be tracked to the millimeter and millisecond and played back to novices so that they may embody the feelings and movements of an expert. Because experts perceive objects and events in their domain of expertise differently than non-experts (Goodwin, 1994), embodying their sensorimotor experiences is likely to be a rich learning experience for novices. Limitations and Future Directions There are several limitations to the current dissertations studies that need to be further explored in future research. Perhaps the most salient limitation of the study is the embodied experience itself. The rich sensorimotor information provided in the current dissertation studies, the vivid vibrations of the chain saw used to cut 92 down the tree in particular, served as a powerful manipulation that led to significant behavioral differences between conditions. At the same time, the vividness of the IVE stimulus may be a limitation because of the lack of generalizability. That is, this particular context of embodied experience was chosen for its novel nature, but the novelty of the experience (i.e., seeing, hearing, feeling the chain saw) may be driving the differences observed between the conditions. Although one of the greatest merits of using IVEs is that novel or even fantastic experiences can be provided with realistic and vivid sensorimotor information, future studies should also explore embodied experiences with greater mundane realism (i.e., turning off lights for energy conservation, using less water for water conservation) within IVE to confirm whether attitudinal and behavioral differences between embodied experiences in IVEs and MS can still be observed. The lack of evidence in terms of a clear psychological mechanism for the results is another limitation of the current studies. For one, although both of the studies imply that a new sensorimotor schema was constructed after the novel embodied experience of cutting a tree down, I have no explicit evidence of this internal representation. Future studies that involve assessment of mental maps that individuals rely on during their decision making process may be effective. For instance, Bagozzi and Dabholkar (1994) attempted to create a ‘goal map,’ looking at how obtaining different goals may direct individuals’ recycling behaviors. In addition, fMRI scans during the embodied experience may yield neurological confirmation of this process and would make significant contributions to the embodied cognition research. Perception of presence and control were measured and analyzed in an attempt to gain further insight into the underlying mechanisms of embodied 93 experiences. However, despite significant differences between experimental conditions, there was a lack of positive correlations between these variables and pro-environmental behavior, leaving room for speculation with regard to the exact mechanism of embodied experiences. Because immersion and interactivity are all affordances of a relatively novel medium – virtual environments – definitions and measures are still in the processes of validation. This may explain the inconsistency between measurements of recall and presence in Study 1 and 2. Future studies should use both self-report and objective measures to further investigate the role of presence and control during embodied experiences in virtual environments. There were also some limitations in the measurements of self-efficacy and actual pro-environmental behavior. First of all, although pre-treatment and posttreatment self-efficacy were measured and successfully demonstrated significant differences between the two time periods, it is possible that post-treatment selfefficacy levels may have been influenced to some extent by the pro-environmental information provided to the participants before experimental treatments rather than the actual treatments (i.e., IVE and MS) themselves. It should also be noted that different brands of napkins were used for Study 1 and Study 2, resulting in differences in the absolute number of napkins used by participants to clean up the water. However, the ratio of difference between conditions in napkin usage remained similar in both studies. Finally, to measure behavioral change in terms of napkin conservation rather than behavioral difference between conditions, a true control condition is needed to assess the baseline of napkin usage. Similarly, a condition that assesses the effect of actual tree-cutting activity in the physical world on pro-environmental self-efficacy and behavior may yield greater insights to how embodied experiences in IVEs compare against actual experiences in the real world. 94 Individual differences in perceiving presence is also an area of research that lacks empirical evidence, and although these dissertation studies provide a good foundation for initial investigation there is much room for improvement. Due to the lack of earlier evidence on individual differences, I chose to look at group mean differences based on a median split to factor individual differences into my analyses. However, the method of applying a median split on a continuous variable has been criticized (Aiken & West, 1991) for the loss of power. Thus, it is possible that there may be further differences between individuals based on their disposition for perspective taking that these dissertation studies were not able to assess. In relation, although Study 2 confirmed significant interactions between individual differences in the propensity for perspective taking and agency of control for napkin usage, my hypotheses which expected higher levels of immersion and self-based agency of control to elicit greater pro-environmental behavior compared to lower levels of immersion and other-based agency of control were not supported. There may be several reasons for this unexpected result. Although the current analyses controlled for individual variances such as prior experience with videogames or baseline levels of self-efficacy, there may have been an important individual difference that was overlooked. It may also be that a more precise operationalization of immersion is needed, as the current dissertation studies incorporated a mixture of several sensorimotor cues in the operationalization of high and low levels of immersion. Finally, although increase in pro-environmental behavior after embodied experiences was demonstrated in both studies, this behavior was measured only after a short break (20-30 minutes) following the experimental treatment. Future studies should explore longer lasting effects of embodied experiences in virtual 95 environments with either a follow-up survey as the one used in the colorblind studies or longitudinal designs. Researchers should also look at the generalizability of the embodied experiences after individuals have been taken out of the virtual world. For instance, the behavioral measure assessed in the dissertation studies was directly related to paper products, but it would be interesting to find out whether the embodied experience of cutting trees could generalize to a wider range of proenvironmental behavior such as energy conservation. These dissertation studies make meaningful contributions to prior research on embodied cognition and virtual environments, as well as demonstrate exciting potential for wide-ranging applications of embodied experiences through virtual environments. The results demonstrate that our perceptions and actions within virtual worlds can directly affect our perceptions and actions in the physical world. With the rapid advancement and dispersion of technology, we may soon be in a world in which we are able to embody any entity to virtually experience the life of that entity augmented with vivid sensorimotor inputs, right in the comforts of our own living room. If these virtual expeditions can lead to attitudinal and behavioral changes in the physical world, it is imperative for scholars to conduct timely investigations on the different effects of embodied experiences as this may easily become a social issue. Through the current dissertation, I strived to take the initial steps toward shedding light on these unanswered yet critical questions on the increasingly blurred boundary between virtual and physical experiences. 96 NOTES 1. Entering race/ethnicity as a factor did not affect any of the subsequent analyses and will not be discussed further. 2. Approximately equal numbers of participants from each group were randomly assigned into IVE (High Propensity n = 10; Low Propensity n = 13) and MS conditions (High Propensity n = 15; Low Propensity n = 8), with the exception of one cell. However, results revealed no significant interactions between experimental condition and perspective taking propensity and this issue is not discussed further. 3. In some of the studies discussed earlier, researchers looked at locus on control as an inherent individual difference, but for the current study it is a state influenced by the manipulation of agency of control rather than a trait and will be measured and analyzed as such. 4. Open-ended responses assessed participants’ suspicion of the behavioral measure. One female and one male were dropped from the final dataset due to suspicion. 5. The experimenter was visibly pregnant at the time. Consequently, none of the participants were suspicious that the spilled water was a part of the experiment. This was confirmed by open-ended responses taken after administering the behavioral measure. 97 APPENDIX A: STIMULUS FOR MENTAL SIMULATION CONDITION IN STUDY 1 You are in a forest with many tall, green, pine trees scattered around you. The environment is placid and soothing, and it would be a nice place to have a picnic. There are birds flying in and out of the trees, dancing in the skies, and you hear them chirping. The birds fly past you, fly in front of you, and fly directly above your head into the sky. The forest floor is covered in rolling grassy patches and there are some hills to the right side of you. Pretty, white clouds float above your head in the blue sky. You hear the sound of running water and rustling leaves. You are standing directly in front of a tall, pine tree with light brown colored bark. It looks like a Christmas tree and the leaves along its branches that hang over your head are spiky at the ends. The tree trunk is about the width of a person, maybe a little bit more. The leaves and branches are so thick that they cover your view of the sky. To the left side of the tree, there is already a triangle shaped wedge cut out of the trunk, and the tree looks like it is ready to be felled. [BREAK. STOP READING AND WAIT FOR FURTHER INSTRUCTIONS] Both of your hands are holding the handle of a chain saw with a warning sign which reads that it is a dangerous tool. The saw is positioned at the right end of the tree trunk, positioned to cut through until the saw reaches the part where a wedge has already been cut out. The chain saw starts with a roar and you feel the vibrations of the saw going into the tree. It feels like cutting cardboard, almost. Very resistant and grainy. You feel every slice of the saw and the vibrations from running the blade against the wood. The grating noise from the chain saw increases and decreases as you pull the saw in and out of the tree, slowly making your way through the trunk. The sound is so loud and disruptive that it drowns out all the sounds from the nature. You can see progress being made as you work and you see lighter bark inside the tree trunk where you made the cut. When your saw meets the part of the trunk where the wedge has already been cut out, the trunk slow slides down to the left. You hear all the branches snapping and cracking as they break, then a loud crash and great commotion as the trunk falls to the ground, landing a couple feet away from the stump. After the tree has fallen to one side, you suddenly see a large clearing in the forest. It looks much more open and you can see all of the other trees that were once hidden by this tall tree. It was a smooth, clean cut, and you see numerous rings on the fallen tree trunk, realizing how old this tree was. The forest is like dead silent now. There are no more birds flying around and their 98 chirping has stopped. It seems eerily empty- kind of in the middle of nowhere. Now it feels more like a clearing instead of a thick forest. 99 APPENDIX B: STUDY 1 SURVEY ITEMS Pretest Perspective Taking Propensity Please read the following statements carefully, and rate the extent to how well these statements describe you (1 = Almost never; 2 = Once in a while; 3 = Sometimes; 4 = Frequently; 5 = Almost all the time). 1. How often do you attempt to understand your friends better by trying to figure out what they are thinking? 2. How often do you try to think of more than one explanation for why someone else acted as they did? 3. Overall, how often do you try to understand the point of view of other people? 4. When you are angry at someone, how often do you try to “put yourself in his or her shoes”? 5. How often do you try to figure out what motivates others to behave as they do? 6. How often do you try to figure out what emotions people are feeling when you meet them for the first time? 7. In general, how often do you try to understand how other people view the situation? Pre-treatment Self-Efficacy Please read the following statements and indicate how well does each statement describes your point of view (1 = Does not describe my point of view well; 2 = Describes my point of view slightly well; 3 = Describes my point of view moderately well; 4 = Describes my point of view pretty well; 5 = Describes my point of view 100 extremely well). 8. My individual actions would improve the quality of the environment if I were to carpool instead of driving alone. 9. My individual actions would improve the quality of the environment if I were to set my home appliances, such as the refrigerator, dishwasher, water heater, etc. to “energy-saver” levels. 10. My individual actions would improve the quality of the environment if I were to learn about the recycling facilities in my area. 11. My individual actions would improve the quality of the environment if I were to attend a community meeting that involves concern over a local environmental issue. 12. My individual actions would improve the quality of the environment if I were to buy resource conservation devices, such as low-flow faucet aerators for my sinks and low-flow shower heads. 13. My individual actions would improve the quality of the environment if I were to open windows for ventilation rather than using a fan or air conditioner. 14. My individual actions would improve the quality of the environment if I were to buy products packaged in containers that either can be reused or recycled or are made of recycled materials. 15. My individual actions would improve the quality of the environment if I were to reduce the amount of my household trash by reusing or recycling items to the fullest extent possible. 16. My individual actions would improve the quality of the environment if I were to take my old tires to a recycling center. 101 17. My individual actions would improve the quality of the environment if I were to buy and use recycled paper products. Experimental Survey Presence (1 = Not at all; 2 = Slightly; 3 = Moderately; 4 = Pretty much; 5 = Very much) 1. To what degree did you identify with the tree-cutter? 2. To what extent do you feel that the tree-cutter is an extension of yourself? 3. To what extent do you feel that if something happens to the tree-cutter, it feels like it is happening to you? 4. To what extent do you feel you embodied the tree-cutter? 5. To what extent did you feel you were in the same space as the tree-cutter? 6. To what extent did the tree-cutter seem real? 7. To what extent did you feel involved in the forest environment? 8. To what extent did you feel like you were inside a forest? 9. To what extent did you feel surrounded by the forest? 10. To what extent did it feel like you visited another place? 11. How much did the forest seem real? Recall 12. Try to remember all the pieces of information on toilet paper production and its effects on the forest. For instance, how many rolls of toilet paper is used in average per year. We have prepared a form for you to use to record your recollections. Simply write down the first information you remember in the first box, the second in the second box, etc. Please put only one piece of information that you 102 remember in one box. IGNORE SPELLING, GRAMMAR, AND PUNCTUATION. We have deliberately provided more space than we think most people will need to insure that everyone would have plenty of room to write. So don't worry if you don't fill every space. Just write down whatever information you recall. Personal Control Rate your personal reaction based on your experience in the forest. 13. Looking at the picture above, enter the number under the drawing that best describes how aroused you felt during your experience in the forest. Post-treatment Self-Efficacy 14 – 23. Items 8-17 in the pretest. 103 APPENDIX C: SURVEY ITEMS FOR STUDY 2 Pretest Items 1-17 from Study 1 Pretest Experimental Survey Control 1. Item 13 from Study 1 Experimental Survey. Presence Think back on your experience of standing in the shoes of the tree-cutter. Please choose the adverb that best completes the sentence, based on your experiences (1 = Not at all; 2 = Slightly; 3 = Moderately; 4 = Pretty much; 5 = Very much). 2. When standing in the shoes of the tree-cutter, I felt like my avatar was _______ an extension of my body within the virtual environment. 3. When standing in the shoes of the tree-cutter, I felt like my avatar was ______ a part of my body. 4. When standing in the shoes of the tree-cutter, I felt ________like I could reach into the virtual environment through my avatar. 5. When using my avatar, I felt_________like my arm was elongated into the virtual environment through my avatar. 6. When standing in the shoes of the tree-cutter, I felt ______ like my own hand was inside of the virtual environment. 7. When the tree-cutter's arms were moving in the forest, I felt ______ like I was moving my own arms. 104 Think back on the experience you had in the forest, while you were standing in the shoes of the tree-cutter. Please do not spend too much time on any one question. Your first response is usually the best. For each question, choose the answer CLOSEST to your own (1 = Strongly disagree; 2 = Disagree; 3 = Neither agree or disagree; 4 agree; 5 = Strongly agree). 8. I felt that the tree branches and birds in the forest could almost touch me. 9. I felt I was actually visiting the forest. 10. I had the sensation that I moved in response to the movement of the chain saw. 11. I felt that I could almost smell the plant life in the forest. 12. I had a strong sense of sounds coming from different directions within the forest. 13. I felt surrounded by the forest. 14. I felt I could have reached out and touched the tree branches and the birds in the forest. 15. I felt that all my senses were stimulated at the same time. 16. When cutting down the tree, I felt I changed the course of events in the forest. 17. I had the sensation that the tree, the birds, and the chain saw were responding to me and my movements. 18. It felt realistic to move the chain saw in the forest. Behavioral Intention After you walk out of this room, please indicate the extent to which you plan to take the following actions (1 = Rarely; 2 = Occasionally; 3 = Sometimes; 4 = Frequently; 5 = Usually). 105 19. How often will you purchase a product because it is packaged in reusable or recyclable containers? 20. How often will you buy products made from recycled material? 21. How likely is it that you will switch from your current brand of toilet paper to use a recycled brand (even if the recycled brand might be lesser in quality)? 22. How often will you watch TV programs to learn about the importance of recycling paper? 23. How often will you talk to others about the importance of recycling paper? Recall 24. Item 12 from Study 1 Experimental Survey. Post-Treatment Self-Efficacy 25 – 34. Items 8-17 from Study 1 Pretest. Locus of Control Think back on your experience in the virtual forest while you took the perspective of the tree-cutter. Think about what caused you (i.e., tree-cutter) to cut down this tree. Then indicate the extent to which you agree with the following statements regarding your reasons. 106 35. Is the cause(s) something... (1 = That reflects an aspect of yourself; 9 = That reflects an aspect of the situation) 36. Is the cause(s) something... (1 = Inside of you; 9 = Outside of you) 37. Is the cause(s) something... (1 = Something about you; 9 = Something about others) 107 APPENDIX D: STATISTICS FOR ALL ANALYSES IN STUDY 1 Napkins (N = 46; IVE n = 23, MS n = 23, Low Propensity n = 21, High Propensity n = 25) Main effects: Experimental condition, F(1, 40) = 4.16, p < .05, partial η2 = .09. Perspective taking propensity, F(1, 40) = 4.73, p < .05, partial η2 = .11. Interaction effect: Experimental condition x Perspective taking propensity, F(1, 40) = .01, p > .05. Self-reported Presence (N = 46; IVE n = 23, MS n = 23, Low Propensity n = 21, High Propensity n = 25) Main effects: Experimental condition, F(1, 40) = .21, p > .05. Perspective taking propensity, F(1, 40) = 2.28, p > .05. Interaction effect: Experimental condition x Perspective taking propensity, F(1, 40) = .60, p > .05. Recall (N = 46; IVE n = 23, MS n = 23, Low Propensity n = 21, High Propensity n = 25) Main effects: Experimental condition, F(1, 40) = 6.22, p < .05, partial η2 = .14. Perspective taking propensity, F(1, 40) = 1.36, p > .05. Interaction effect: Experimental condition x Perspective taking propensity, F(1, 40) = .29, p > .05. Control (N = 46; IVE n = 23, MS n = 23, Low Propensity n = 21, High Propensity n = 25) 108 Main effects: Experimental condition, F(1, 40) = 4.44, p < .05, partial η2 = .10. Perspective taking propensity, F(1, 40) = .58, p > .05. Interaction effect: Experimental condition x Perspective taking propensity, F(1, 40) = .14, p > .05. Self-Efficacy (N = 46; IVE n = 23, MS n = 23, Low Propensity n = 21, High Propensity n = 25) Main effect: Self-efficacy, F(1, 41) = 4.62, p < .05, partial η2 = .10. Interaction effects: Self-efficacy x Experimental condition, F(1, 41) = .16, p > .05. Self-efficacy x Perspective taking propensity, F(1, 41) = 1.29, p > .05. Self-efficacy x Experimental condition x Perspective taking propensity, F(1, 41) = 2.05, p > .05. Control (N = 46; IVE n = 23, MS n = 23, Low Propensity n = 21, High Propensity n = 25) Main effects: Experimental condition, F(1, 40) = 4.44, p < .05, partial η2 = .10. Perspective taking propensity, F(1, 40) = .58, p > .05. Interaction effect: Experimental condition x Perspective taking propensity, F(1, 40) = .14, p > .05. 109 APPENDIX E: MEANS AND STANDARD DEVIATIONS FOR ALL DEPENDENT VARIABLES IN STUDY 2 Napkins Immersion Low High Total Perspective Taking Agency Propensity Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 8.0714 8.7273 8.3600 7.6667 6.9231 7.2800 7.8846 7.7500 7.8200 6.4615 9.1667 7.7600 9.4615 7.7692 8.6154 7.9615 8.4400 8.1961 7.2963 8.9565 8.0600 8.6000 7.3462 7.9608 7.9231 8.1020 8.0099 Std. Deviation 3.12470 2.28433 2.75197 3.28449 4.13242 3.69143 3.14104 3.46724 3.26821 3.38170 2.85509 3.36997 3.66550 3.19254 3.47651 3.77869 3.05614 3.41772 3.29119 2.54912 3.06001 3.53553 3.64354 3.61088 3.44051 3.24836 3.33315 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 110 Behavioral Intention - Total Immersion Low High Total Perspective Taking Agency Propensity Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 2.9429 2.9818 2.9600 2.4667 2.7846 2.6320 2.7231 2.8750 2.7960 2.4000 2.5167 2.4560 2.8308 2.6923 2.7615 2.6154 2.6080 2.6118 2.6815 2.7391 2.7080 2.6560 2.7385 2.6980 2.6692 2.7388 2.7030 Std. Deviation .77828 .64159 .70711 .70496 .56250 .64208 .76958 .59509 .68867 .59442 .52886 .55534 .98267 .83513 .89625 .82544 .69637 .75727 .73643 .61919 .67879 .86317 .69919 .77704 .79200 .65600 .72642 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 111 Behavioral Intention – Item 1 Immersion Low High Total Perspective Taking Agency Propensity Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 3.3571 3.6364 3.4800 3.2500 3.2308 3.2400 3.3077 3.4167 3.3600 3.1538 2.9167 3.0400 3.5385 3.2308 3.3846 3.3462 3.0800 3.2157 3.2593 3.2609 3.2600 3.4000 3.2308 3.3137 3.3269 3.2449 3.2871 Std. Deviation 1.08182 .92442 1.00499 1.05529 .83205 .92556 1.04954 .88055 .96384 .98710 .99620 .97809 1.19829 1.01274 1.09825 1.09334 .99666 1.04525 1.02254 1.00983 1.00631 1.11803 .90808 1.00976 1.06128 .94716 1.00336 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 112 Behavioral Intention – Item 2 Immersion Low High Total Perspective Taking Agency Propensity Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 3.7143 3.8182 3.7600 3.1667 3.5385 3.3600 3.4615 3.6667 3.5600 3.0000 3.0000 3.0000 3.4615 3.3077 3.3846 3.2308 3.1600 3.1961 3.3704 3.3913 3.3800 3.3200 3.4231 3.3725 3.3462 3.4082 3.3762 Std. Deviation .99449 1.07872 1.01160 .83485 .66023 .75719 .94787 .86811 .90711 1.08012 .85280 .95743 1.12660 .85485 .98293 1.10662 .85049 .98020 1.07946 1.03305 1.04764 .98826 .75753 .87088 1.02679 .88784 .95762 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 113 Behavioral Intention – Item 3 Immersion Low High Total Perspective Taking Agency Propensity Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 3.2857 3.4545 3.3600 2.5000 3.0769 2.8000 2.9231 3.2500 3.0800 2.8462 2.4167 2.6400 2.9231 3.3846 3.1538 2.8846 2.9200 2.9020 3.0741 2.9130 3.0000 2.7200 3.2308 2.9804 2.9038 3.0816 2.9901 Std. Deviation .99449 1.03573 .99499 1.00000 .95407 1.00000 1.05539 .98907 1.02698 .89872 .90034 .90738 1.38212 1.55662 1.46130 1.14287 1.35154 1.23701 .95780 1.08347 1.01015 1.20830 1.27460 1.25682 1.08934 1.18738 1.13574 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 114 Behavioral Intention – Item 4 Immersion Low High Total Perspective Taking Agency Propensity Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 1.9286 1.6364 1.8000 1.5833 1.5385 1.5600 1.7692 1.5833 1.6800 1.2308 1.5833 1.4000 1.9231 1.4615 1.6923 1.5769 1.5200 1.5490 1.5926 1.6087 1.6000 1.7600 1.5000 1.6275 1.6731 1.5510 1.6139 Std. Deviation .91687 1.20605 1.04083 .66856 .77625 .71181 .81524 .97431 .89077 .59914 .66856 .64550 1.11516 .66023 .92819 .94543 .65320 .80781 .84395 .94094 .88063 .92556 .70711 .82367 .87942 .81806 .84818 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 115 Behavioral Intention – Item 5 Immersion Low High Total Perspective Taking Agency Propensity Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 2.4286 2.6364 2.5200 1.8333 2.5385 2.2000 2.1538 2.5833 2.3600 1.7692 2.6667 2.2000 2.4615 2.0769 2.2692 2.1154 2.3600 2.2353 2.1111 2.6522 2.3600 2.1600 2.3077 2.2353 2.1346 2.4694 2.2970 Std. Deviation .85163 1.02691 .91833 1.02986 1.12660 1.11803 .96715 1.05981 1.02539 .59914 1.15470 1.00000 1.19829 .95407 1.07917 .99305 1.07548 1.03128 .80064 1.07063 .96384 1.14310 1.04954 1.08790 .97073 1.06266 1.02513 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 116 Recall Immersion Low High Total Perspective Taking Agency Propensity Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 3.7143 4.4091 4.0200 3.6250 3.5769 3.6000 3.6731 3.9583 3.8100 3.2308 3.0000 3.1200 2.5769 3.6923 3.1346 2.9038 3.3600 3.1275 3.4815 3.6739 3.5700 3.0800 3.6346 3.3627 3.2885 3.6531 3.4653 Std. Deviation 1.29666 2.13094 1.71075 1.49431 1.45554 1.44338 1.36340 1.80529 1.58078 1.54940 1.52256 1.50886 .95407 1.49358 1.35320 1.30399 1.51740 1.41719 1.41748 1.93419 1.65988 1.32822 1.44608 1.40385 1.37679 1.67458 1.53176 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 117 Pre- and Post-Treatment Self-Efficacy Pre-treatment Immersion Low Agency Self-Move self-efficacy Other-Move Total High Self-Move Other-Move Total Total Self-Move Other-Move Total Post-treatment Low Self-Move self-efficacy Other-Move Total High Self-Move Other-Move Total Total Self-Move Other-Move Total Propensity Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Low Propensity High Propensity Total Mean 2.9357 3.6818 3.2640 2.9167 3.3385 3.1360 2.9269 3.4958 3.2000 2.9385 3.4667 3.1920 3.0154 3.6077 3.3115 2.9769 3.5400 3.2529 2.9370 3.5696 3.2280 2.9680 3.4731 3.2255 2.9519 3.5184 3.2267 3.5571 3.7091 3.6240 3.5917 3.6923 3.6440 3.5731 3.7000 3.6340 3.3154 3.7667 3.5320 3.6385 3.9538 3.7962 3.4769 3.8640 3.6667 3.4407 3.7391 3.5780 3.6160 3.8231 3.7216 3.5250 3.7837 3.6505 SD .67892 .31880 .65947 .80208 .41138 .65248 .72308 .40376 .65247 .95877 .58981 .83162 .92452 .72280 .86733 .92360 .65256 .84365 .80915 .48189 .74369 .85133 .59232 .76703 .82164 .53994 .75178 .86444 .58558 .74402 .90700 .73989 .80833 .86651 .65938 .76894 .86588 .67600 .79829 .92605 .74231 .83785 .89367 .70290 .82138 .85721 .62066 .76513 .89800 .73827 .81886 .87288 .67987 .79204 118 Locus of Control Immersion Low High Total Perspective Taking Agency Propensity Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Self-Move Low Propensity High Propensity Total Other-Move Low Propensity High Propensity Total Total Low Propensity High Propensity Total Mean 3.3810 3.1212 3.2667 2.5833 2.7433 2.6665 3.0128 2.9165 2.9666 3.3331 3.1667 3.2532 2.7436 2.7179 2.7308 3.0383 2.9333 2.9869 3.3579 3.1449 3.2599 2.6667 2.7306 2.6993 3.0256 2.9251 2.9768 Std. Deviation 1.67871 1.31886 1.50616 1.12927 1.20267 1.14645 1.48018 1.24415 1.35895 1.24677 1.06837 1.14349 1.33440 1.33226 1.30646 1.30046 1.20953 1.24524 1.45845 1.16700 1.32348 1.21716 1.24355 1.21875 1.37955 1.21378 1.29627 N 14 11 25 12 13 25 26 24 50 13 12 25 13 13 26 26 25 51 27 23 50 25 26 51 52 49 101 119 APPENDIX F: STATISTICS FOR ALL ANALYSES IN STUDY 2 Presence Main effects: Immersion, F(1, 91) = 9.59, p < .01, partial η2 = .10. Agency of control, F(1, 91) = .74, p > .05. Perspective taking propensity, F(1, 91) = 0, p > .05. Interaction effects: Immersion x Agency of control, F(1, 91) = .69, p > .05. Immersion x Perspective taking propensity, F(1, 91) = .72, p > .05. Agency of control x Perspective taking propensity, F(1, 91) = .65, p > .05. Immersion x Agency of control x Perspective taking propensity, F(1, 91) = 0, p > .05. Control Main effects: Immersion, F(1, 91) = 1.37, p > .05. Agency of control, F(1, 91) = 6.30, p < .05, partial η2 = .07. Perspective taking propensity, F(1, 91) = .14, p > .05. Interaction effects: Immersion x Agency of control, F(1, 91) = .41, p > .05. Immersion x Perspective taking propensity, F(1, 91) = .10, p > .05. Agency of control x Perspective taking propensity, F(1, 91) = .29, p > .05. Immersion x Agency of control x Perspective taking propensity, F(1, 91) = 1.04, p > .05. Behavioral Intention Main effects: Immersion, F(1, 91) = 3.34, p > .05. Agency of control, F(1, 91) = 0, p > .05. 120 Perspective taking propensity, F(1, 91) = 4.52, p < .05, partial η2 = .05. Interaction effects: Immersion x Agency of control, F(1, 91) = 3.80, p > .05. Immersion x Perspective taking propensity, F(1, 91) = .60, p > .05. Agency of control x Perspective taking propensity, F(1, 91) = .17, p > .05. Immersion x Agency of control x Perspective taking propensity, F(1, 91) = 2.84, p > .05. Napkins Main effects: Immersion, F(1, 91) = .11, p > .05. Agency of control, F(1, 91) = .68, p > .05. Perspective taking propensity, F(1, 91) = .49, p > .05. Interaction effects: Immersion x Agency of control, F(1, 91) = 2.12, p > .05. Immersion x Perspective taking propensity, F(1, 91) = .09, p > .05. Agency of control x Perspective taking propensity, F(1, 91) = 4.86, p < .05, partial η2 = .05. Immersion x Agency of control x Perspective taking propensity, F(1, 91) = 1.59, p > .05. Recall Main effects: Immersion, F(1, 91) = 6.24, p < .05, partial η2 = .06. Agency of control, F(1, 91) = .60, p > .05. Perspective taking propensity, F(1, 91) = .10, p > .05. Interaction effects: Immersion x Agency of control, F(1, 91) = .30, p > .05. Immersion x Perspective taking propensity, F(1, 91) = .04, p > .05. Agency of control x Perspective taking propensity, F(1, 91) = .41, p > .05. 121 Immersion x Agency of control x Perspective taking propensity, F(1, 91) = 2.47, p > .05. Pre- and Post-treatment Self-Efficacy Main effects: Self-efficacy, F(1, 92) = 41.93, p < .01, partial η2 = .31. Interaction effects: Self-efficacy x Immersion, F(1, 92) = 0, p > .05. Self-efficacy x Agency, F(1, 92) = 2.53, p > .05. Self-efficacy x Perspective taking propensity, F(1, 92) = 8.91, p < .01, partial η2 = .09. Self-efficacy x Immersion x Agency of control, F(1, 92) = .04, p > .05. Self-efficacy x Immersion x Perspective taking propensity, F(1, 92) = 1.79, p > .05. Self-efficacy x Agency x Perspective taking propensity, F(1, 92) = .03, p > .05. Self-efficacy x Immersion x Agency of control x Perspective taking propensity, F(1, 92) = 1.21, p > .05. Locus of Control Main effects: Immersion, F(1, 91) = 0, p > .05. Agency of control, F(1, 91) = 4.73, p < .05, partial η2 = .05. Perspective taking propensity, F(1, 91) = 1.27, p > .05. Interaction effects: Immersion x Agency of control, F(1, 91) = .02, p > .05. Immersion x Perspective taking propensity, F(1, 91) = .01, p > .05. Agency of control x Perspective taking propensity, F(1, 91) = .46, p > .05. 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